Theorem: MeasureTheory.lintegral_comp_eq_lintegral_meas_le_mul_of_measurable
File: Mathlib/MeasureTheory/Integral/Layercake.lean

tactic: have f_nonneg : ∀ ω, 0 ≤ f ω := fun ω ↦ f_nn ω
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: by_cases H1 : g =ᵐ[volume.restrict (Ioi (0 : ℝ))] 0
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: by_cases H2 : ∃ s > 0, 0 < ∫ t in (0)..s, g t ∧ μ {a : α | s < f a} = ∞
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∃ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t ∧ μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ¬∃ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t ∧ μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: push_neg at H2
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ¬∃ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t ∧ μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have M_bdd : BddAbove {s : ℝ | g =ᵐ[volume.restrict (Ioc (0 : ℝ) s)] 0} := by
  contrapose! H1
  have : ∀ (n : ℕ), g =ᵐ[volume.restrict (Ioc (0 : ℝ) n)] 0 := by
    intro n
    rcases not_bddAbove_iff.1 H1 n with ⟨s, hs, ns⟩
    exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right ns.le) hs
  have Hg : g =ᵐ[volume.restrict (⋃ (n : ℕ), (Ioc (0 : ℝ) n))] 0 :=
    (ae_restrict_iUnion_iff _ _).2 this
  have : (⋃ (n : ℕ), (Ioc (0 : ℝ) n)) = Ioi 0 :=
    iUnion_Ioc_eq_Ioi_self_iff.2 (fun x _ ↦ exists_nat_ge x)
  rwa [this] at Hg
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: let M : ℝ := sSup {s : ℝ | g =ᵐ[volume.restrict (Ioc (0 : ℝ) s)] 0}
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have zero_mem : 0 ∈ {s : ℝ | g =ᵐ[volume.restrict (Ioc (0 : ℝ) s)] 0} := by simpa using trivial
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have M_nonneg : 0 ≤ M := le_csSup M_bdd zero_mem
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have hgM : g =ᵐ[volume.restrict (Ioc (0 : ℝ) M)] 0 := by
  rw [← restrict_Ioo_eq_restrict_Ioc]
  obtain ⟨u, -, uM, ulim⟩ : ∃ u, StrictMono u ∧ (∀ (n : ℕ), u n < M) ∧ Tendsto u atTop (𝓝 M) :=
    exists_seq_strictMono_tendsto M
  have I : ∀ n, g =ᵐ[volume.restrict (Ioc (0 : ℝ) (u n))] 0 := by
    intro n
    obtain ⟨s, hs, uns⟩ : ∃ s, g =ᶠ[ae (Measure.restrict volume (Ioc 0 s))] 0 ∧ u n < s :=
      exists_lt_of_lt_csSup (Set.nonempty_of_mem zero_mem) (uM n)
    exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right uns.le) hs
  have : g =ᵐ[volume.restrict (⋃ n, Ioc (0 : ℝ) (u n))] 0 := (ae_restrict_iUnion_iff _ _).2 I
  apply ae_restrict_of_ae_restrict_of_subset _ this
  rintro x ⟨x_pos, xM⟩
  obtain ⟨n, hn⟩ : ∃ n, x < u n := ((tendsto_order.1 ulim).1 _ xM).exists
  exact mem_iUnion.2 ⟨n, ⟨x_pos, hn.le⟩⟩
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: let ν := μ.restrict {a : α | M < f a}
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have A : ∫⁻ ω, ENNReal.ofReal (∫ t in (0)..f ω, g t) ∂μ
       = ∫⁻ ω, ENNReal.ofReal (∫ t in (0)..f ω, g t) ∂ν := by
  have meas : MeasurableSet {a | M < f a} := measurableSet_lt measurable_const f_mble
  have I : ∫⁻ ω in {a | M < f a}ᶜ, ENNReal.ofReal (∫ t in (0).. f ω, g t) ∂μ
           = ∫⁻ _ in {a | M < f a}ᶜ, 0 ∂μ := by
    apply setLIntegral_congr_fun meas.compl (eventually_of_forall (fun s hs ↦ ?_))
    have : ∫ (t : ℝ) in (0)..f s, g t = ∫ (t : ℝ) in (0)..f s, 0 := by
      simp_rw [intervalIntegral.integral_of_le (f_nonneg s)]
      apply integral_congr_ae
      apply ae_mono (restrict_mono ?_ le_rfl) hgM
      apply Ioc_subset_Ioc_right
      simpa using hs
    simp [this]
  simp only [lintegral_const, zero_mul] at I
  rw [← lintegral_add_compl _ meas, I, add_zero]
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have B : ∫⁻ t in Ioi 0, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t)
         = ∫⁻ t in Ioi 0, ν {a : α | t ≤ f a} * ENNReal.ofReal (g t) := by
  have B1 : ∫⁻ t in Ioc 0 M, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t)
       = ∫⁻ t in Ioc 0 M, ν {a : α | t ≤ f a} * ENNReal.ofReal (g t) := by
    apply lintegral_congr_ae
    filter_upwards [hgM] with t ht
    simp [ht]
  have B2 : ∫⁻ t in Ioi M, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t)
            = ∫⁻ t in Ioi M, ν {a : α | t ≤ f a} * ENNReal.ofReal (g t) := by
    apply setLIntegral_congr_fun measurableSet_Ioi (eventually_of_forall (fun t ht ↦ ?_))
    rw [Measure.restrict_apply (measurableSet_le measurable_const f_mble)]
    congr 3
    exact (inter_eq_left.2 (fun a ha ↦ (mem_Ioi.1 ht).trans_le ha)).symm
  have I : Ioi (0 : ℝ) = Ioc (0 : ℝ) M ∪ Ioi M := (Ioc_union_Ioi_eq_Ioi M_nonneg).symm
  have J : Disjoint (Ioc 0 M) (Ioi M) := Ioc_disjoint_Ioi le_rfl
  rw [I, lintegral_union measurableSet_Ioi J, lintegral_union measurableSet_Ioi J, B1, B2]
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B :
  ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [A, B]
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B :
  ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B :
  ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: exact lintegral_comp_eq_lintegral_meas_le_mul_of_measurable_of_sigmaFinite
  ν f_nn f_mble g_intble g_mble g_nn
state_before: case neg
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B :
  ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: no goals

tactic: have A : ∫⁻ ω, ENNReal.ofReal (∫ t in (0)..f ω, g t) ∂μ = 0 := by
  have : ∀ ω, ∫ t in (0)..f ω, g t = ∫ t in (0)..f ω, 0 := by
    intro ω
    simp_rw [intervalIntegral.integral_of_le (f_nonneg ω)]
    apply integral_congr_ae
    exact ae_restrict_of_ae_restrict_of_subset Ioc_subset_Ioi_self H1
  simp [this]
state_before: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have B : ∫⁻ t in Ioi 0, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t) = 0 := by
  have : (fun t ↦ μ {a : α | t ≤ f a} * ENNReal.ofReal (g t))
    =ᵐ[volume.restrict (Ioi (0:ℝ))] 0 := by
      filter_upwards [H1] with t ht using by simp [ht]
  simp [lintegral_congr_ae this]
state_before: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
B : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [A, B]
state_before: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
B : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: no goals

tactic: have : ∀ ω, ∫ t in (0)..f ω, g t = ∫ t in (0)..f ω, 0 := by
  intro ω
  simp_rw [intervalIntegral.integral_of_le (f_nonneg ω)]
  apply integral_congr_ae
  exact ae_restrict_of_ae_restrict_of_subset Ioc_subset_Ioi_self H1
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
this : ∀ (ω : α), ∫ (t : ℝ) in 0 ..f ω, g t = ∫ (t : ℝ) in 0 ..f ω, 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0

tactic: simp [this]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
this : ∀ (ω : α), ∫ (t : ℝ) in 0 ..f ω, g t = ∫ (t : ℝ) in 0 ..f ω, 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
state_after: no goals

tactic: intro ω
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∀ (ω : α), ∫ (t : ℝ) in 0 ..f ω, g t = ∫ (t : ℝ) in 0 ..f ω, 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ ∫ (t : ℝ) in 0 ..f ω, g t = ∫ (t : ℝ) in 0 ..f ω, 0

tactic: simp_rw [intervalIntegral.integral_of_le (f_nonneg ω)]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ ∫ (t : ℝ) in 0 ..f ω, g t = ∫ (t : ℝ) in 0 ..f ω, 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ ∫ (t : ℝ) in Ioc 0 (f ω), g t ∂volume = ∫ (t : ℝ) in Ioc 0 (f ω), 0 ∂volume

tactic: apply integral_congr_ae
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ ∫ (t : ℝ) in Ioc 0 (f ω), g t ∂volume = ∫ (t : ℝ) in Ioc 0 (f ω), 0 ∂volume
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (f ω)))] fun a => 0

tactic: exact ae_restrict_of_ae_restrict_of_subset Ioc_subset_Ioi_self H1
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
ω : α
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (f ω)))] fun a => 0
state_after: no goals

tactic: have : (fun t ↦ μ {a : α | t ≤ f a} * ENNReal.ofReal (g t))
  =ᵐ[volume.restrict (Ioi (0:ℝ))] 0 := by
    filter_upwards [H1] with t ht using by simp [ht]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
this : (fun t => μ {a | t ≤ f a} * ENNReal.ofReal (g t)) =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0

tactic: simp [lintegral_congr_ae this]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
this : (fun t => μ {a | t ≤ f a} * ENNReal.ofReal (g t)) =ᶠ[ae (volume.restrict (Ioi 0))] 0
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0
state_after: no goals

tactic: filter_upwards [H1] with t ht using by simp [ht]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ (fun t => μ {a | t ≤ f a} * ENNReal.ofReal (g t)) =ᶠ[ae (volume.restrict (Ioi 0))] 0
state_after: no goals

tactic: simp [ht]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : g =ᶠ[ae (volume.restrict (Ioi 0))] 0
A : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
t : ℝ
ht : g t = 0 t
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = 0 t
state_after: no goals

tactic: rcases H2 with ⟨s, s_pos, hs, h's⟩
state_before: case pos
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∃ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t ∧ μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos.intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (t : ℝ) in 0 ..s, g t
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [intervalIntegral.integral_of_le s_pos.le] at hs
state_before: case pos.intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (t : ℝ) in 0 ..s, g t
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case pos.intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [A, B]
state_before: case pos.intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
B : ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ =
    ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: no goals

tactic: rw [eq_top_iff]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ⊤ ≤ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [lintegral_const_mul, ENNReal.top_mul I_pos]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
I_pos : ∫⁻ (a : ℝ) in Ioc 0 s, ENNReal.ofReal (g a) ≠ 0
⊢ ⊤ = ∫⁻ (t : ℝ) in Ioc 0 s, ⊤ * ENNReal.ofReal (g t)
state_after: case hf
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
I_pos : ∫⁻ (a : ℝ) in Ioc 0 s, ENNReal.ofReal (g a) ≠ 0
⊢ Measurable fun t => ENNReal.ofReal (g t)

tactic: exact ENNReal.measurable_ofReal.comp g_mble
state_before: case hf
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
I_pos : ∫⁻ (a : ℝ) in Ioc 0 s, ENNReal.ofReal (g a) ≠ 0
⊢ Measurable fun t => ENNReal.ofReal (g t)
state_after: no goals

tactic: rw [← ofReal_integral_eq_lintegral_ofReal (g_intble s s_pos).1]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (a : ℝ) in Ioc 0 s, ENNReal.ofReal (g a) ≠ 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ENNReal.ofReal (∫ (x : ℝ) in Ioc 0 s, g x ∂volume) ≠ 0

α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ 0 ≤ᶠ[ae (volume.restrict (Ioc 0 s))] g

tactic: simpa only [not_lt, ge_iff_le, ne_eq, ENNReal.ofReal_eq_zero, not_le] using hs
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ENNReal.ofReal (∫ (x : ℝ) in Ioc 0 s, g x ∂volume) ≠ 0
state_after: no goals

tactic: filter_upwards [ae_restrict_mem measurableSet_Ioc] with t ht using g_nn _ ht.1
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ 0 ≤ᶠ[ae (volume.restrict (Ioc 0 s))] g
state_after: no goals

tactic: apply setLIntegral_mono' measurableSet_Ioc (fun x hx ↦ ?_)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
⊢ ∫⁻ (t : ℝ) in Ioc 0 s, ⊤ * ENNReal.ofReal (g t) ≤ ∫⁻ (t : ℝ) in Ioc 0 s, μ {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ ⊤ * ENNReal.ofReal (g x) ≤ μ {a | x ≤ f a} * ENNReal.ofReal (g x)

tactic: rw [← h's]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ ⊤ * ENNReal.ofReal (g x) ≤ μ {a | x ≤ f a} * ENNReal.ofReal (g x)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ μ {a | s < f a} * ENNReal.ofReal (g x) ≤ μ {a | x ≤ f a} * ENNReal.ofReal (g x)

tactic: gcongr
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ μ {a | s < f a} * ENNReal.ofReal (g x) ≤ μ {a | x ≤ f a} * ENNReal.ofReal (g x)
state_after: case bc.h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ {a | s < f a} ⊆ {a | x ≤ f a}

tactic: exact fun a ha ↦ hx.2.trans (le_of_lt ha)
state_before: case bc.h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
x : ℝ
hx : x ∈ Ioc 0 s
⊢ {a | s < f a} ⊆ {a | x ≤ f a}
state_after: no goals

tactic: rw [eq_top_iff]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ⊤ ≤ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ

tactic: simp only [lintegral_const, MeasurableSet.univ, Measure.restrict_apply, univ_inter,
  h's, ne_eq, ENNReal.ofReal_eq_zero, not_le]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ⊤ = ∫⁻ (x : α) in {a | s < f a}, ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ∂μ
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ⊤ = ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) * ⊤

tactic: rw [ENNReal.mul_top]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ⊤ = ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) * ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ≠ 0

tactic: simpa [intervalIntegral.integral_of_le s_pos.le] using hs
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ≠ 0
state_after: no goals

tactic: apply setLIntegral_mono' (measurableSet_lt measurable_const f_mble) (fun a ha ↦ ?_)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
⊢ ∫⁻ (x : α) in {a | s < f a}, ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ∂μ ≤
    ∫⁻ (ω : α) in {a | s < f a}, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ≤ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f a, g t)

tactic: apply ENNReal.ofReal_le_ofReal
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..s, g t) ≤ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f a, g t)
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ ∫ (t : ℝ) in 0 ..s, g t ≤ ∫ (t : ℝ) in 0 ..f a, g t

tactic: apply intervalIntegral.integral_mono_interval le_rfl s_pos.le (le_of_lt ha)
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ ∫ (t : ℝ) in 0 ..s, g t ≤ ∫ (t : ℝ) in 0 ..f a, g t
state_after: case h.hf
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ 0 ≤ᶠ[ae (volume.restrict (Ioc 0 (f a)))] g

case h.hfi
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ IntervalIntegrable g volume 0 (f a)

tactic: filter_upwards [ae_restrict_mem measurableSet_Ioc] with t ht using g_nn _ ht.1
state_before: case h.hf
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ 0 ≤ᶠ[ae (volume.restrict (Ioc 0 (f a)))] g
state_after: no goals

tactic: exact g_intble _ (s_pos.trans ha)
state_before: case h.hfi
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
s : ℝ
s_pos : s > 0
hs : 0 < ∫ (x : ℝ) in Ioc 0 s, g x ∂volume
h's : μ {a | s < f a} = ⊤
A : ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ⊤
a : α
ha : a ∈ {a | s < f a}
⊢ IntervalIntegrable g volume 0 (f a)
state_after: no goals

tactic: contrapose! H1
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
⊢ BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0

tactic: have : ∀ (n : ℕ), g =ᵐ[volume.restrict (Ioc (0 : ℝ) n)] 0 := by
  intro n
  rcases not_bddAbove_iff.1 H1 n with ⟨s, hs, ns⟩
  exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right ns.le) hs
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0

tactic: have Hg : g =ᵐ[volume.restrict (⋃ (n : ℕ), (Ioc (0 : ℝ) n))] 0 :=
  (ae_restrict_iUnion_iff _ _).2 this
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
Hg : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 ↑n))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0

tactic: have : (⋃ (n : ℕ), (Ioc (0 : ℝ) n)) = Ioi 0 :=
  iUnion_Ioc_eq_Ioi_self_iff.2 (fun x _ ↦ exists_nat_ge x)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
Hg : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 ↑n))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this✝ : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
Hg : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 ↑n))] 0
this : ⋃ n, Ioc 0 ↑n = Ioi 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0

tactic: rwa [this] at Hg
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
this✝ : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
Hg : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 ↑n))] 0
this : ⋃ n, Ioc 0 ↑n = Ioi 0
⊢ g =ᶠ[ae (volume.restrict (Ioi 0))] 0
state_after: no goals

tactic: intro n
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
n : ℕ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0

tactic: rcases not_bddAbove_iff.1 H1 n with ⟨s, hs, ns⟩
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
n : ℕ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
state_after: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
n : ℕ
s : ℝ
hs : s ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
ns : ↑n < s
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0

tactic: exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right ns.le) hs
state_before: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
H1 : ¬BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
n : ℕ
s : ℝ
hs : s ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
ns : ↑n < s
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 ↑n))] 0
state_after: no goals

tactic: simpa using trivial
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
⊢ 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
state_after: no goals

tactic: rw [← restrict_Ioo_eq_restrict_Ioc]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0

tactic: obtain ⟨u, -, uM, ulim⟩ : ∃ u, StrictMono u ∧ (∀ (n : ℕ), u n < M) ∧ Tendsto u atTop (𝓝 M) :=
  exists_seq_strictMono_tendsto M
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0
state_after: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0

tactic: have I : ∀ n, g =ᵐ[volume.restrict (Ioc (0 : ℝ) (u n))] 0 := by
  intro n
  obtain ⟨s, hs, uns⟩ : ∃ s, g =ᶠ[ae (Measure.restrict volume (Ioc 0 s))] 0 ∧ u n < s :=
    exists_lt_of_lt_csSup (Set.nonempty_of_mem zero_mem) (uM n)
  exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right uns.le) hs
state_before: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0
state_after: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0

tactic: have : g =ᵐ[volume.restrict (⋃ n, Ioc (0 : ℝ) (u n))] 0 := (ae_restrict_iUnion_iff _ _).2 I
state_before: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0
state_after: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0

tactic: apply ae_restrict_of_ae_restrict_of_subset _ this
state_before: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
⊢ g =ᶠ[ae (volume.restrict (Ioo 0 M))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
⊢ Ioo 0 M ⊆ ⋃ n, Ioc 0 (u n)

tactic: rintro x ⟨x_pos, xM⟩
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
⊢ Ioo 0 M ⊆ ⋃ n, Ioc 0 (u n)
state_after: case intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
x : ℝ
x_pos : 0 < x
xM : x < M
⊢ x ∈ ⋃ n, Ioc 0 (u n)

tactic: obtain ⟨n, hn⟩ : ∃ n, x < u n := ((tendsto_order.1 ulim).1 _ xM).exists
state_before: case intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
x : ℝ
x_pos : 0 < x
xM : x < M
⊢ x ∈ ⋃ n, Ioc 0 (u n)
state_after: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
x : ℝ
x_pos : 0 < x
xM : x < M
n : ℕ
hn : x < u n
⊢ x ∈ ⋃ n, Ioc 0 (u n)

tactic: exact mem_iUnion.2 ⟨n, ⟨x_pos, hn.le⟩⟩
state_before: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
I : ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
this : g =ᶠ[ae (volume.restrict (⋃ n, Ioc 0 (u n)))] 0
x : ℝ
x_pos : 0 < x
xM : x < M
n : ℕ
hn : x < u n
⊢ x ∈ ⋃ n, Ioc 0 (u n)
state_after: no goals

tactic: intro n
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
⊢ ∀ (n : ℕ), g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0

tactic: obtain ⟨s, hs, uns⟩ : ∃ s, g =ᶠ[ae (Measure.restrict volume (Ioc 0 s))] 0 ∧ u n < s :=
  exists_lt_of_lt_csSup (Set.nonempty_of_mem zero_mem) (uM n)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
state_after: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
s : ℝ
hs : g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0
uns : u n < s
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0

tactic: exact ae_restrict_of_ae_restrict_of_subset (Ioc_subset_Ioc_right uns.le) hs
state_before: case intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
u : ℕ → ℝ
uM : ∀ (n : ℕ), u n < M
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
s : ℝ
hs : g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0
uns : u n < s
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (u n)))] 0
state_after: no goals

tactic: obtain ⟨u, -, uM, ulim⟩ : ∃ u, StrictAnti u ∧ (∀ (n : ℕ), M < u n) ∧ Tendsto u atTop (𝓝 M) :=
  exists_seq_strictAnti_tendsto M
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
⊢ SigmaFinite ν
state_after: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
⊢ SigmaFinite ν

tactic: exact ⟨⟨s⟩⟩
state_before: case intro.intro.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
s : ν.FiniteSpanningSetsIn univ :=
  { set := fun n => {a | f a ≤ M} ∪ {a | u n < f a}, set_mem := ⋯, finite := ⋯, spanning := ⋯ }
⊢ SigmaFinite ν
state_after: no goals

tactic: intro n
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
⊢ ∀ (i : ℕ), ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i) < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤

tactic: have I : ν {a | f a ≤ M} = 0 := by
  rw [Measure.restrict_apply (measurableSet_le f_mble measurable_const)]
  convert measure_empty (μ := μ)
  rw [← disjoint_iff_inter_eq_empty]
  exact disjoint_left.mpr (fun a ha ↦ by simpa using ha)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤

tactic: have J : μ {a | u n < f a} < ∞ := by
  rw [lt_top_iff_ne_top]
  apply H2 _ (M_nonneg.trans_lt (uM n))
  by_contra H3
  rw [not_lt, intervalIntegral.integral_of_le (M_nonneg.trans (uM n).le)] at H3
  have g_nn_ae : ∀ᵐ t ∂(volume.restrict (Ioc 0 (u n))), 0 ≤ g t := by
    filter_upwards [ae_restrict_mem measurableSet_Ioc] with s hs using g_nn _ hs.1
  have Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0 :=
    le_antisymm H3 (integral_nonneg_of_ae g_nn_ae)
  have J : ∀ᵐ t ∂(volume.restrict (Ioc 0 (u n))), g t = 0 :=
    (integral_eq_zero_iff_of_nonneg_ae g_nn_ae
      (g_intble (u n) (M_nonneg.trans_lt (uM n))).1).1 Ig
  have : u n ≤ M := le_csSup M_bdd J
  exact lt_irrefl _ (this.trans_lt (uM n))
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤

tactic: refine lt_of_le_of_lt (measure_union_le _ _) ?_
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν ((fun n => {a | f a ≤ M} ∪ {a | u n < f a}) n) < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | f a ≤ M} + ν {a | u n < f a} < ⊤

tactic: rw [I, zero_add]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | f a ≤ M} + ν {a | u n < f a} < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | u n < f a} < ⊤

tactic: apply lt_of_le_of_lt _ J
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | u n < f a} < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | u n < f a} ≤ μ {a | u n < f a}

tactic: exact restrict_le_self _
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
J : μ {a | u n < f a} < ⊤
⊢ ν {a | u n < f a} ≤ μ {a | u n < f a}
state_after: no goals

tactic: rw [Measure.restrict_apply (measurableSet_le f_mble measurable_const)]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ ν {a | f a ≤ M} = 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ μ ({a | f a ≤ M} ∩ {a | M < f a}) = 0

tactic: convert measure_empty (μ := μ)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ μ ({a | f a ≤ M} ∩ {a | M < f a}) = 0
state_after: case h.e'_2.h.e'_6
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ {a | f a ≤ M} ∩ {a | M < f a} = ∅

tactic: rw [← disjoint_iff_inter_eq_empty]
state_before: case h.e'_2.h.e'_6
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ {a | f a ≤ M} ∩ {a | M < f a} = ∅
state_after: case h.e'_2.h.e'_6
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ Disjoint {a | f a ≤ M} {a | M < f a}

tactic: exact disjoint_left.mpr (fun a ha ↦ by simpa using ha)
state_before: case h.e'_2.h.e'_6
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
⊢ Disjoint {a | f a ≤ M} {a | M < f a}
state_after: no goals

tactic: simpa using ha
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
a : α
ha : a ∈ {a | f a ≤ M}
⊢ a ∉ {a | M < f a}
state_after: no goals

tactic: rw [lt_top_iff_ne_top]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ μ {a | u n < f a} < ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ μ {a | u n < f a} ≠ ⊤

tactic: apply H2 _ (M_nonneg.trans_lt (uM n))
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ μ {a | u n < f a} ≠ ⊤
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ 0 < ∫ (t : ℝ) in 0 ..u n, g t

tactic: by_contra H3
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
⊢ 0 < ∫ (t : ℝ) in 0 ..u n, g t
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ¬0 < ∫ (t : ℝ) in 0 ..u n, g t
⊢ False

tactic: rw [not_lt, intervalIntegral.integral_of_le (M_nonneg.trans (uM n).le)] at H3
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ¬0 < ∫ (t : ℝ) in 0 ..u n, g t
⊢ False
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
⊢ False

tactic: have g_nn_ae : ∀ᵐ t ∂(volume.restrict (Ioc 0 (u n))), 0 ≤ g t := by
  filter_upwards [ae_restrict_mem measurableSet_Ioc] with s hs using g_nn _ hs.1
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
⊢ False
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
⊢ False

tactic: have Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0 :=
  le_antisymm H3 (integral_nonneg_of_ae g_nn_ae)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
⊢ False
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
⊢ False

tactic: have J : ∀ᵐ t ∂(volume.restrict (Ioc 0 (u n))), g t = 0 :=
  (integral_eq_zero_iff_of_nonneg_ae g_nn_ae
    (g_intble (u n) (M_nonneg.trans_lt (uM n))).1).1 Ig
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
⊢ False
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
J : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), g t = 0
⊢ False

tactic: have : u n ≤ M := le_csSup M_bdd J
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
J : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), g t = 0
⊢ False
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
J : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), g t = 0
this : u n ≤ M
⊢ False

tactic: exact lt_irrefl _ (this.trans_lt (uM n))
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
g_nn_ae : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
Ig : ∫ (t : ℝ) in Ioc 0 (u n), g t = 0
J : ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), g t = 0
this : u n ≤ M
⊢ False
state_after: no goals

tactic: filter_upwards [ae_restrict_mem measurableSet_Ioc] with s hs using g_nn _ hs.1
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
n : ℕ
I : ν {a | f a ≤ M} = 0
H3 : ∫ (x : ℝ) in Ioc 0 (u n), g x ∂volume ≤ 0
⊢ ∀ᵐ (t : ℝ) ∂volume.restrict (Ioc 0 (u n)), 0 ≤ g t
state_after: no goals

tactic: apply eq_univ_iff_forall.2 (fun a ↦ ?_)
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
⊢ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i = univ
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i

tactic: rcases le_or_lt (f a) M with ha|ha
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i
state_after: case inl
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : f a ≤ M
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i

case inr
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : M < f a
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i

tactic: exact mem_iUnion.2 ⟨0, Or.inl ha⟩
state_before: case inl
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : f a ≤ M
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i
state_after: no goals

tactic: obtain ⟨n, hn⟩ : ∃ n, u n < f a := ((tendsto_order.1 ulim).2 _ ha).exists
state_before: case inr
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : M < f a
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i
state_after: case inr.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : M < f a
n : ℕ
hn : u n < f a
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i

tactic: exact mem_iUnion.2 ⟨n, Or.inr hn⟩
state_before: case inr.intro
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
u : ℕ → ℝ
uM : ∀ (n : ℕ), M < u n
ulim : Tendsto u atTop (𝓝 M)
a : α
ha : M < f a
n : ℕ
hn : u n < f a
⊢ a ∈ ⋃ i, (fun n => {a | f a ≤ M} ∪ {a | u n < f a}) i
state_after: no goals

tactic: have meas : MeasurableSet {a | M < f a} := measurableSet_lt measurable_const f_mble
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν

tactic: have I : ∫⁻ ω in {a | M < f a}ᶜ, ENNReal.ofReal (∫ t in (0).. f ω, g t) ∂μ
         = ∫⁻ _ in {a | M < f a}ᶜ, 0 ∂μ := by
  apply setLIntegral_congr_fun meas.compl (eventually_of_forall (fun s hs ↦ ?_))
  have : ∫ (t : ℝ) in (0)..f s, g t = ∫ (t : ℝ) in (0)..f s, 0 := by
    simp_rw [intervalIntegral.integral_of_le (f_nonneg s)]
    apply integral_congr_ae
    apply ae_mono (restrict_mono ?_ le_rfl) hgM
    apply Ioc_subset_Ioc_right
    simpa using hs
  simp [this]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
I : ∫⁻ (ω : α) in {a | M < f a}ᶜ, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (x : α) in {a | M < f a}ᶜ, 0 ∂μ
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν

tactic: simp only [lintegral_const, zero_mul] at I
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
I : ∫⁻ (ω : α) in {a | M < f a}ᶜ, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (x : α) in {a | M < f a}ᶜ, 0 ∂μ
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
I : ∫⁻ (ω : α) in {a | M < f a}ᶜ, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν

tactic: rw [← lintegral_add_compl _ meas, I, add_zero]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
I : ∫⁻ (ω : α) in {a | M < f a}ᶜ, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = 0
⊢ ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
state_after: no goals

tactic: apply setLIntegral_congr_fun meas.compl (eventually_of_forall (fun s hs ↦ ?_))
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
⊢ ∫⁻ (ω : α) in {a | M < f a}ᶜ, ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (x : α) in {a | M < f a}ᶜ, 0 ∂μ
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f s, g t) = 0

tactic: have : ∫ (t : ℝ) in (0)..f s, g t = ∫ (t : ℝ) in (0)..f s, 0 := by
  simp_rw [intervalIntegral.integral_of_le (f_nonneg s)]
  apply integral_congr_ae
  apply ae_mono (restrict_mono ?_ le_rfl) hgM
  apply Ioc_subset_Ioc_right
  simpa using hs
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f s, g t) = 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this✝ : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
this : ∫ (t : ℝ) in 0 ..f s, g t = ∫ (t : ℝ) in 0 ..f s, 0
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f s, g t) = 0

tactic: simp [this]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this✝ : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
this : ∫ (t : ℝ) in 0 ..f s, g t = ∫ (t : ℝ) in 0 ..f s, 0
⊢ ENNReal.ofReal (∫ (t : ℝ) in 0 ..f s, g t) = 0
state_after: no goals

tactic: simp_rw [intervalIntegral.integral_of_le (f_nonneg s)]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ ∫ (t : ℝ) in 0 ..f s, g t = ∫ (t : ℝ) in 0 ..f s, 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ ∫ (t : ℝ) in Ioc 0 (f s), g t ∂volume = ∫ (t : ℝ) in Ioc 0 (f s), 0 ∂volume

tactic: apply integral_congr_ae
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ ∫ (t : ℝ) in Ioc 0 (f s), g t ∂volume = ∫ (t : ℝ) in Ioc 0 (f s), 0 ∂volume
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (f s)))] fun a => 0

tactic: apply ae_mono (restrict_mono ?_ le_rfl) hgM
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ g =ᶠ[ae (volume.restrict (Ioc 0 (f s)))] fun a => 0
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ Ioc 0 (f s) ⊆ Ioc 0 M

tactic: apply Ioc_subset_Ioc_right
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ Ioc 0 (f s) ⊆ Ioc 0 M
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ f s ≤ M

tactic: simpa using hs
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s✝ : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
meas : MeasurableSet {a | M < f a}
s : α
hs : s ∈ {a | M < f a}ᶜ
⊢ f s ≤ M
state_after: no goals

tactic: have B1 : ∫⁻ t in Ioc 0 M, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t)
     = ∫⁻ t in Ioc 0 M, ν {a : α | t ≤ f a} * ENNReal.ofReal (g t) := by
  apply lintegral_congr_ae
  filter_upwards [hgM] with t ht
  simp [ht]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have B2 : ∫⁻ t in Ioi M, μ {a : α | t ≤ f a} * ENNReal.ofReal (g t)
          = ∫⁻ t in Ioi M, ν {a : α | t ≤ f a} * ENNReal.ofReal (g t) := by
  apply setLIntegral_congr_fun measurableSet_Ioi (eventually_of_forall (fun t ht ↦ ?_))
  rw [Measure.restrict_apply (measurableSet_le measurable_const f_mble)]
  congr 3
  exact (inter_eq_left.2 (fun a ha ↦ (mem_Ioi.1 ht).trans_le ha)).symm
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have I : Ioi (0 : ℝ) = Ioc (0 : ℝ) M ∪ Ioi M := (Ioc_union_Ioi_eq_Ioi M_nonneg).symm
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
I : Ioi 0 = Ioc 0 M ∪ Ioi M
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: have J : Disjoint (Ioc 0 M) (Ioi M) := Ioc_disjoint_Ioi le_rfl
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
I : Ioi 0 = Ioc 0 M ∪ Ioi M
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
I : Ioi 0 = Ioc 0 M ∪ Ioi M
J : Disjoint (Ioc 0 M) (Ioi M)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [I, lintegral_union measurableSet_Ioi J, lintegral_union measurableSet_Ioi J, B1, B2]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
B2 :
  ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
I : Ioi 0 = Ioc 0 M ∪ Ioi M
J : Disjoint (Ioc 0 M) (Ioi M)
⊢ ∫⁻ (t : ℝ) in Ioi 0, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi 0, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: no goals

tactic: apply lintegral_congr_ae
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ (fun a => μ {a_1 | a ≤ f a_1} * ENNReal.ofReal (g a)) =ᶠ[ae (volume.restrict (Ioc 0 M))] fun a =>
    ν {a_1 | a ≤ f a_1} * ENNReal.ofReal (g a)

tactic: filter_upwards [hgM] with t ht
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
⊢ (fun a => μ {a_1 | a ≤ f a_1} * ENNReal.ofReal (g a)) =ᶠ[ae (volume.restrict (Ioc 0 M))] fun a =>
    ν {a_1 | a ≤ f a_1} * ENNReal.ofReal (g a)
state_after: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
t : ℝ
ht : g t = 0 t
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: simp [ht]
state_before: case h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
t : ℝ
ht : g t = 0 t
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: no goals

tactic: apply setLIntegral_congr_fun measurableSet_Ioi (eventually_of_forall (fun t ht ↦ ?_))
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
⊢ ∫⁻ (t : ℝ) in Ioi M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioi M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ν {a | t ≤ f a} * ENNReal.ofReal (g t)

tactic: rw [Measure.restrict_apply (measurableSet_le measurable_const f_mble)]
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = ν {a | t ≤ f a} * ENNReal.ofReal (g t)
state_after: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = μ ({a | t ≤ f a} ∩ {a | M < f a}) * ENNReal.ofReal (g t)

tactic: congr 3
state_before: α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ μ {a | t ≤ f a} * ENNReal.ofReal (g t) = μ ({a | t ≤ f a} ∩ {a | M < f a}) * ENNReal.ofReal (g t)
state_after: case e_a.h.e_6.h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ {a | t ≤ f a} = {a | t ≤ f a} ∩ {a | M < f a}

tactic: exact (inter_eq_left.2 (fun a ha ↦ (mem_Ioi.1 ht).trans_le ha)).symm
state_before: case e_a.h.e_6.h
α : Type u_1
inst✝ : MeasurableSpace α
f : α → ℝ
g : ℝ → ℝ
s : Set α
μ : Measure α
f_nn : 0 ≤ f
f_mble : Measurable f
g_intble : ∀ t > 0, IntervalIntegrable g volume 0 t
g_mble : Measurable g
g_nn : ∀ t > 0, 0 ≤ g t
f_nonneg : ∀ (ω : α), 0 ≤ f ω
H1 : ¬g =ᶠ[ae (volume.restrict (Ioi 0))] 0
H2 : ∀ s > 0, 0 < ∫ (t : ℝ) in 0 ..s, g t → μ {a | s < f a} ≠ ⊤
M_bdd : BddAbove {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M : ℝ := sSup {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
zero_mem : 0 ∈ {s | g =ᶠ[ae (volume.restrict (Ioc 0 s))] 0}
M_nonneg : 0 ≤ M
hgM : g =ᶠ[ae (volume.restrict (Ioc 0 M))] 0
ν : Measure α := μ.restrict {a | M < f a}
this : SigmaFinite ν
A :
  ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂μ = ∫⁻ (ω : α), ENNReal.ofReal (∫ (t : ℝ) in 0 ..f ω, g t) ∂ν
B1 :
  ∫⁻ (t : ℝ) in Ioc 0 M, μ {a | t ≤ f a} * ENNReal.ofReal (g t) =
    ∫⁻ (t : ℝ) in Ioc 0 M, ν {a | t ≤ f a} * ENNReal.ofReal (g t)
t : ℝ
ht : t ∈ Ioi M
⊢ {a | t ≤ f a} = {a | t ≤ f a} ∩ {a | M < f a}
state_after: no goals