mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
f : α → ℝ≥0∞
hf : Measurable f
ε : ℝ≥0∞
εpos : ε ≠ 0
δ : ℕ → ℝ≥0∞
δpos : ∀ (i : ℕ), 0 < δ i
hδ : ∑' (i : ℕ), δ i < ε
g : ℕ → α → ℝ≥0
f_le_g : ∀ (n : ℕ) (x : α), (eapproxDiff f n) x ≤ g n x
gcont : ∀ (n : ℕ), LowerSemicontinuous (g n)
hg : ∀ (n : ℕ), ∫⁻ (x : α), ↑(g n x) ∂μ ≤ ∫⁻ (x : α), ↑((eapproxDiff f n) x) ∂μ + δ n
⊢ ∫⁻ (a : α), f a ∂μ ≤ ∫⁻ (a : α), f a ∂μ

Tactic:
le_refl

Goal state after:
Module: Mathlib.Geometry.Convex.Cone.Basic

Goal state before:
pp: 𝕜 : Type u_1
R : Type u_2
G : Type u_3
M : Type u_4
N : Type u_5
O : Type u_6
inst✝³ : Semiring R
inst✝² : PartialOrder R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
C₁✝ C₂✝ : ConvexCone R M
x : M
C₁ C₂ : ConvexCone R M
⊢ ∀ ⦃c : R⦄, 0 < c → ∀ ⦃x : M⦄, x ∈ ↑C₁ + ↑C₂ → c • x ∈ ↑C₁ + ↑C₂

Tactic:
rintro c hc _ ⟨x, hx, y, hy, rfl⟩
      rw [smul_add]
      use c • x, C₁.smul_mem hc hx, c • y, C₂.smul_mem hc hy

Goal state after:
Module: Mathlib.Geometry.Convex.Cone.Basic

Goal state before:
pp: 𝕜 : Type u_1
M : Type u_4
inst✝⁴ : Field 𝕜
inst✝³ : LinearOrder 𝕜
inst✝² : IsStrictOrderedRing 𝕜
inst✝¹ : AddCommGroup M
inst✝ : Module 𝕜 M
s : Set M
x : M
hs : Convex 𝕜 s
hx : x ∈ hull 𝕜 s
y₁ : M
r₁ : 𝕜
hr₁ : 0 < r₁
hy₁ : y₁ ∈ r₁ • s
y₂ : M
r₂ : 𝕜
hr₂ : 0 < r₂
hy₂ : y₂ ∈ r₂ • s
⊢ y₁ + y₂ ∈ (r₁ + r₂) • s

Tactic:
rw [hs.add_smul hr₁.le hr₂.le]

Goal state after:
𝕜 : Type u_1
M : Type u_4
inst✝⁴ : Field 𝕜
inst✝³ : LinearOrder 𝕜
inst✝² : IsStrictOrderedRing 𝕜
inst✝¹ : AddCommGroup M
inst✝ : Module 𝕜 M
s : Set M
x : M
hs : Convex 𝕜 s
hx : x ∈ hull 𝕜 s
y₁ : M
r₁ : 𝕜
hr₁ : 0 < r₁
hy₁ : y₁ ∈ r₁ • s
y₂ : M
r₂ : 𝕜
hr₂ : 0 < r₂
hy₂ : y₂ ∈ r₂ • s
⊢ y₁ + y₂ ∈ r₁ • s + r₂ • s
Module: Mathlib.Analysis.Convex.Gauge

Goal state before:
pp: E : Type u_2
inst✝¹ : AddCommGroup E
inst✝ : Module ℝ E
s : Set E
x : E
absorbs : Absorbent ℝ s
hgauge : gauge s x < 1
⊢ ∃ y ∈ s, x ∈ openSegment ℝ 0 y

Tactic:
by
  rcases exists_lt_of_gauge_lt absorbs hgauge with ⟨r, hr₀, hr₁, y, hy, rfl⟩
  refine ⟨y, hy, 1 - r, r, ?_⟩
  simp [*]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
f : α → ℝ≥0
int_f : ∫⁻ (x : α), ↑(f x) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
this :
  ∫⁻ (x : α), ↑(f x) ∂μ <
    (⨆ φ, ⨆ (_ : ∀ (x : α), ↑(φ x) ≤ ↑(f x)), (SimpleFunc.map ENNReal.ofNNReal φ).lintegral μ) + ε / 2
⊢ ∃ fs, (∀ (x : α), fs x ≤ f x) ∧ ∫⁻ (x : α), ↑(f x) ∂μ ≤ ∫⁻ (x : α), ↑(fs x) ∂μ + ε / 2

Tactic:
rw [ENNReal.biSup_add'] at this <;> [skip; exact ⟨0, fun x => by simp⟩]

Goal state after:
α : Type u_1
inst✝³ : TopologicalSpace α
inst✝² : MeasurableSpace α
inst✝¹ : BorelSpace α
μ : Measure α
inst✝ : μ.WeaklyRegular
f : α → ℝ≥0
int_f : ∫⁻ (x : α), ↑(f x) ∂μ ≠ ∞
ε : ℝ≥0∞
ε0 : ε ≠ 0
this :
  ∫⁻ (x : α), ↑(f x) ∂μ <
    ⨆ i, ⨆ (_ : ∀ (x : α), ↑(i x) ≤ ↑(f x)), (SimpleFunc.map ENNReal.ofNNReal i).lintegral μ + ε / 2
⊢ ∃ fs, (∀ (x : α), fs x ≤ f x) ∧ ∫⁻ (x : α), ↑(f x) ∂μ ≤ ∫⁻ (x : α), ↑(fs x) ∂μ + ε / 2
Module: Mathlib.Analysis.RCLike.Extend

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : RCLike 𝕜
F : Type u_2
inst✝³ : AddCommGroup F
inst✝² : Module ℝ F
inst✝¹ : Module 𝕜 F
inst✝ : IsScalarTower ℝ 𝕜 F
f : Dual 𝕜 F
⊢ extendRCLike ((fun f ↦ reLm ∘ₗ ↑ℝ f) f) = f

Tactic:
ext; apply RCLike.ext <;> simp

Goal state after:
Module: Mathlib.Analysis.LocallyConvex.Separation

Goal state before:
pp: case refine_2
E : Type u_2
inst✝⁴ : TopologicalSpace E
inst✝³ : AddCommGroup E
inst✝² : IsTopologicalAddGroup E
inst✝¹ : Module ℝ E
inst✝ : ContinuousSMul ℝ E
s : Set E
hs₀ : 0 ∈ s
hs₁ : Convex ℝ s
hs₂ : IsOpen s
x₀ : E
hx₀ : x₀ ∉ s
f : E →ₗ.[ℝ] ℝ := LinearPMap.mkSpanSingleton x₀ 1 ⋯
φ : E →ₗ[ℝ] ℝ
hφ₁ : ∀ (x : ↥f.domain), φ ↑x = ↑f x
hφ₂ : ∀ (x : E), φ x ≤ gauge s x
hφ₃ : φ x₀ = 1
hφ₄ : ∀ x ∈ s, φ x < 1
x : E
hx : x ∈ s
⊢ -φ x₀ + φ x ≠ 0

Tactic:
specialize hφ₄ x hx

Goal state after:
case refine_2
E : Type u_2
inst✝⁴ : TopologicalSpace E
inst✝³ : AddCommGroup E
inst✝² : IsTopologicalAddGroup E
inst✝¹ : Module ℝ E
inst✝ : ContinuousSMul ℝ E
s : Set E
hs₀ : 0 ∈ s
hs₁ : Convex ℝ s
hs₂ : IsOpen s
x₀ : E
hx₀ : x₀ ∉ s
f : E →ₗ.[ℝ] ℝ := LinearPMap.mkSpanSingleton x₀ 1 ⋯
φ : E →ₗ[ℝ] ℝ
hφ₁ : ∀ (x : ↥f.domain), φ ↑x = ↑f x
hφ₂ : ∀ (x : E), φ x ≤ gauge s x
hφ₃ : φ x₀ = 1
x : E
hφ₄ : φ x < 1
hx : x ∈ s
⊢ -φ x₀ + φ x ≠ 0
Module: Mathlib.Analysis.Convex.Gauge

Goal state before:
pp: case inr
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
r : ℝ
hr✝ : 0 ≤ r
x : E
hr : 0 < r
⊢ |r|⁻¹ • gauge (ball 0 1) x = ‖x‖ / r

pp: case inr.symmetric
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
r : ℝ
hr✝ : 0 ≤ r
x : E
hr : 0 < r
⊢ ∀ x ∈ ball 0 1, -x ∈ ball 0 1

Tactic:
gauge_unit_ball,

Goal state after:
case inr
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
r : ℝ
hr✝ : 0 ≤ r
x : E
hr : 0 < r
⊢ |r|⁻¹ • ‖x‖ = ‖x‖ / r

case inr.symmetric
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
r : ℝ
hr✝ : 0 ≤ r
x : E
hr : 0 < r
⊢ ∀ x ∈ ball 0 1, -x ∈ ball 0 1
Module: Mathlib.MeasureTheory.Integral.Bochner.VitaliCaratheodory

Goal state before:
pp: α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ
hf : Integrable f μ
ε : ℝ
εpos : 0 < ε
δ : ℝ≥0 := NNReal.mk (ε / 2) ⋯
δpos : 0 < δ
fp : α → ℝ≥0 := fun x ↦ (f x).toNNReal
int_fp : Integrable (fun x ↦ ↑(fp x)) μ
gp : α → ℝ≥0∞
fp_lt_gp : ∀ (x : α), ↑(fp x) < gp x
gpcont : LowerSemicontinuous gp
gp_lt_top : ∀ᵐ (x : α) ∂μ, gp x < ∞
gp_integrable : Integrable (fun x ↦ (gp x).toReal) μ
gpint : ∫ (x : α), (gp x).toReal ∂μ < ∫ (x : α), ↑(fp x) ∂μ + ↑δ
fm : α → ℝ≥0 := fun x ↦ (-f x).toNNReal
int_fm : Integrable (fun x ↦ ↑(fm x)) μ
gm : α → ℝ≥0
gm_le_fm : ∀ (x : α), gm x ≤ fm x
gmcont : UpperSemicontinuous gm
gm_integrable : Integrable (fun x ↦ ↑(gm x)) μ
gmint : ∫ (x : α), ↑(fm x) ∂μ - ↑δ ≤ ∫ (x : α), ↑(gm x) ∂μ
g : α → EReal := fun x ↦ ↑(gp x) - ↑↑(gm x)
ae_g : ∀ᵐ (x : α) ∂μ, (g x).toReal = (↑(gp x)).toReal - (↑↑(gm x)).toReal
⊢ ∫ (x : α), ↑(fp x) ∂μ + ↑δ - (∫ (x : α), ↑(fm x) ∂μ - ↑δ) = ∫ (x : α), f x ∂μ + 2 * ↑δ

Tactic:
simp_rw [integral_eq_integral_pos_part_sub_integral_neg_part hf]

Goal state after:
α : Type u_1
inst✝⁴ : TopologicalSpace α
inst✝³ : MeasurableSpace α
inst✝² : BorelSpace α
μ : Measure α
inst✝¹ : μ.WeaklyRegular
inst✝ : SigmaFinite μ
f : α → ℝ
hf : Integrable f μ
ε : ℝ
εpos : 0 < ε
δ : ℝ≥0 := NNReal.mk (ε / 2) ⋯
δpos : 0 < δ
fp : α → ℝ≥0 := fun x ↦ (f x).toNNReal
int_fp : Integrable (fun x ↦ ↑(fp x)) μ
gp : α → ℝ≥0∞
fp_lt_gp : ∀ (x : α), ↑(fp x) < gp x
gpcont : LowerSemicontinuous gp
gp_lt_top : ∀ᵐ (x : α) ∂μ, gp x < ∞
gp_integrable : Integrable (fun x ↦ (gp x).toReal) μ
gpint : ∫ (x : α), (gp x).toReal ∂μ < ∫ (x : α), ↑(fp x) ∂μ + ↑δ
fm : α → ℝ≥0 := fun x ↦ (-f x).toNNReal
int_fm : Integrable (fun x ↦ ↑(fm x)) μ
gm : α → ℝ≥0
gm_le_fm : ∀ (x : α), gm x ≤ fm x
gmcont : UpperSemicontinuous gm
gm_integrable : Integrable (fun x ↦ ↑(gm x)) μ
gmint : ∫ (x : α), ↑(fm x) ∂μ - ↑δ ≤ ∫ (x : α), ↑(gm x) ∂μ
g : α → EReal := fun x ↦ ↑(gp x) - ↑↑(gm x)
ae_g : ∀ᵐ (x : α) ∂μ, (g x).toReal = (↑(gp x)).toReal - (↑↑(gm x)).toReal
⊢ ∫ (x : α), ↑(fp x) ∂μ + ↑δ - (∫ (x : α), ↑(fm x) ∂μ - ↑δ) =
    ∫ (a : α), ↑(f a).toNNReal ∂μ - ∫ (a : α), ↑(-f a).toNNReal ∂μ + 2 * ↑δ
Module: Mathlib.Analysis.LocallyConvex.SeparatingDual

Goal state before:
pp: R : Type u_1
V : Type u_2
inst✝⁶ : Field R
inst✝⁵ : AddCommGroup V
inst✝⁴ : TopologicalSpace R
inst✝³ : TopologicalSpace V
inst✝² : IsTopologicalRing R
inst✝¹ : Module R V
inst✝ : SeparatingDual R V
x y : V
hx : x ≠ 0
hy : y ≠ 0
⊢ ∃ f, f x = 1 ∧ f y ≠ 0

Tactic:
obtain ⟨u, ux⟩ : ∃ u : StrongDual R V, u x = 1 := exists_eq_one hx

Goal state after:
R : Type u_1
V : Type u_2
inst✝⁶ : Field R
inst✝⁵ : AddCommGroup V
inst✝⁴ : TopologicalSpace R
inst✝³ : TopologicalSpace V
inst✝² : IsTopologicalRing R
inst✝¹ : Module R V
inst✝ : SeparatingDual R V
x y : V
hx : x ≠ 0
hy : y ≠ 0
u : StrongDual R V
ux : u x = 1
⊢ ∃ f, f x = 1 ∧ f y ≠ 0
Module: Mathlib.Analysis.LocallyConvex.Separation

Goal state before:
pp: case inr.inl
E : Type u_2
inst✝⁵ : TopologicalSpace E
inst✝⁴ : AddCommGroup E
inst✝³ : Module ℝ E
s : Set E
inst✝² : IsTopologicalAddGroup E
inst✝¹ : ContinuousSMul ℝ E
inst✝ : LocallyConvexSpace ℝ E
hs₁ : Convex ℝ s
hs₂ : IsCompact s
hs : s.Nonempty
ht₁ : Convex ℝ ∅
ht₂ : IsClosed ∅
disj : Disjoint s ∅
⊢ ∃ f u v, (∀ a ∈ s, f a < u) ∧ u < v ∧ ∀ b ∈ ∅, v < f b

Tactic:
exact ⟨0, 1, 2, by simp⟩

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic

Goal state before:
pp: E : Type u_5
inst✝ : NormedAddCommGroup E
f : ℝ → E
μ : Measure ℝ
a b : ℝ
hf : AEStronglyMeasurable f (μ.restrict (Ι a b))
⊢ IntervalIntegrable (fun t ↦ ‖f t‖) μ a b ↔ IntervalIntegrable f μ a b

Tactic:
simp_rw [intervalIntegrable_iff, IntegrableOn, integrable_norm_iff hf]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic

Goal state before:
pp: case neg
ι : Type u_1
a b : ℝ
μ : Measure ℝ
ε : Type u_8
inst✝³ : TopologicalSpace ε
inst✝² : ENormedAddCommMonoid ε
inst✝¹ : ContinuousAdd ε
inst✝ : PseudoMetrizableSpace ε
f : ι → ℝ → ε
h : ∀ (i : ι), IntervalIntegrable (f i) μ a b
h₁ : ¬(support f).Finite
⊢ IntervalIntegrable (∑ᶠ (i : ι), f i) μ a b

Tactic:
· rw [finsum_of_infinite_support h₁]
    apply intervalIntegrable_const_iff (c := 0) (by simp) |>.2
    tauto

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic

Goal state before:
pp: ε : Type u_3
inst✝² : TopologicalSpace ε
inst✝¹ : ENormedAddMonoid ε
f : ℝ → ε
a b : ℝ
inst✝ : PseudoMetrizableSpace ε
c : ℝ
h : ‖f (min a b)‖ₑ ≠ ∞
⊢ IntervalIntegrable (fun x ↦ f (x + c)) volume (a - c) (b - c) ↔ IntervalIntegrable f volume a b

Tactic:
IntervalIntegrable.comp_add_right_iff (by grind)

Goal state after:
ε : Type u_3
inst✝² : TopologicalSpace ε
inst✝¹ : ENormedAddMonoid ε
f : ℝ → ε
a b : ℝ
inst✝ : PseudoMetrizableSpace ε
c : ℝ
h : ‖f (min a b)‖ₑ ≠ ∞
⊢ IntervalIntegrable f volume (a - c + c) (b - c + c) ↔ IntervalIntegrable f volume a b
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic

Goal state before:
pp: ε : Type u_3
inst✝² : TopologicalSpace ε
inst✝¹ : ENormedAddMonoid ε
f : ℝ → ε
a b : ℝ
inst✝ : PseudoMetrizableSpace ε
c : ℝ
h : ‖f (min a b)‖ₑ ≠ ∞
⊢ IntervalIntegrable (fun x ↦ f (x + -c)) volume (a + c) (b + c) ↔ IntervalIntegrable f volume a b

Tactic:
IntervalIntegrable.comp_add_right_iff (by grind)

Goal state after:
ε : Type u_3
inst✝² : TopologicalSpace ε
inst✝¹ : ENormedAddMonoid ε
f : ℝ → ε
a b : ℝ
inst✝ : PseudoMetrizableSpace ε
c : ℝ
h : ‖f (min a b)‖ₑ ≠ ∞
⊢ IntervalIntegrable f volume (a + c + -c) (b + c + -c) ↔ IntervalIntegrable f volume a b
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.FundThmCalculus

Goal state before:
pp: g' g φ : ℝ → ℝ
a b : ℝ
hab : a ≤ b
hcont : ContinuousOn g (Icc a b)
hderiv : ∀ x ∈ Ico a b, HasDerivWithinAt g (g' x) (Ioi x) x
φint : IntegrableOn φ (Icc a b) volume
hφg : ∀ x ∈ Ico a b, g' x ≤ φ x
ε : ℝ
εpos : 0 < ε
G' : ℝ → EReal
f_lt_G' : ∀ (x : ℝ), ↑(φ x) < G' x
G'cont : LowerSemicontinuous G'
G'int : Integrable (fun x ↦ (G' x).toReal) (volume.restrict (Icc a b))
G'lt_top : ∀ᵐ (x : ℝ) ∂volume.restrict (Icc a b), G' x < ⊤
hG' : ∫ (x : ℝ) in Icc a b, (G' x).toReal < (∫ (x : ℝ) in Icc a b, φ x) + ε
s : Set ℝ := {t | g t - g a ≤ ∫ (u : ℝ) in a..t, (G' u).toReal} ∩ Icc a b
s_closed : IsClosed s
t : ℝ
ht : t ∈ {t | g t - g a ≤ ∫ (u : ℝ) in a..t, (G' u).toReal} ∩ Ico a b
v : ℝ
t_lt_v : v ∈ Ioi t
y : ℝ
g'_lt_y' : ↑(g' t) < ↑y
y_lt_G' : ↑y < G' t
B : ∀ᶠ (u : ℝ) in 𝓝 t, ↑y < G' u
⊢ ∀ᶠ (u : ℝ) in 𝓝[>] t, (u - t) * y ≤ ∫ (w : ℝ) in t..u, (G' w).toReal

Tactic:
rcases mem_nhds_iff_exists_Ioo_subset.1 B with ⟨m, M, ⟨hm, hM⟩, H⟩

Goal state after:
g' g φ : ℝ → ℝ
a b : ℝ
hab : a ≤ b
hcont : ContinuousOn g (Icc a b)
hderiv : ∀ x ∈ Ico a b, HasDerivWithinAt g (g' x) (Ioi x) x
φint : IntegrableOn φ (Icc a b) volume
hφg : ∀ x ∈ Ico a b, g' x ≤ φ x
ε : ℝ
εpos : 0 < ε
G' : ℝ → EReal
f_lt_G' : ∀ (x : ℝ), ↑(φ x) < G' x
G'cont : LowerSemicontinuous G'
G'int : Integrable (fun x ↦ (G' x).toReal) (volume.restrict (Icc a b))
G'lt_top : ∀ᵐ (x : ℝ) ∂volume.restrict (Icc a b), G' x < ⊤
hG' : ∫ (x : ℝ) in Icc a b, (G' x).toReal < (∫ (x : ℝ) in Icc a b, φ x) + ε
s : Set ℝ := {t | g t - g a ≤ ∫ (u : ℝ) in a..t, (G' u).toReal} ∩ Icc a b
s_closed : IsClosed s
t : ℝ
ht : t ∈ {t | g t - g a ≤ ∫ (u : ℝ) in a..t, (G' u).toReal} ∩ Ico a b
v : ℝ
t_lt_v : v ∈ Ioi t
y : ℝ
g'_lt_y' : ↑(g' t) < ↑y
y_lt_G' : ↑y < G' t
B : ∀ᶠ (u : ℝ) in 𝓝 t, ↑y < G' u
m M : ℝ
H : Ioo m M ⊆ {x | (fun u ↦ ↑y < G' u) x}
hm : m < t
hM : t < M
⊢ ∀ᶠ (u : ℝ) in 𝓝[>] t, (u - t) * y ≤ ∫ (w : ℝ) in t..u, (G' w).toReal
Module: Mathlib.MeasureTheory.Integral.DominatedConvergence

Goal state before:
pp: E : Type u_1
X : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : TopologicalSpace X
μ : Measure ℝ
inst✝¹ : NullSingletonClass μ
inst✝ : IsLocallyFiniteMeasure μ
f : X → ℝ → E
a₀ : ℝ
hf : Continuous[instTopologicalSpaceProd, PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (Function.uncurry f)
q : X
b₀ ε : ℝ
εpos : ε > 0
a : ℝ
a_lt : a < a₀ ∧ a < b₀
b : ℝ
lt_b : a₀ < b ∧ b₀ < b
this : IsCompact ({q} ×ˢ Icc a b)
M : ℝ
hM : M ∈ upperBounds ((fun x ↦ ‖Function.uncurry f x‖) '' {q} ×ˢ Icc a b)
⊢ ∃ δ,
    0 < δ ∧
      δ < 1 ∧ Icc (b₀ - δ) (b₀ + δ) ⊆ Icc a b ∧ (M + 1) * μ.real (Icc (b₀ - δ) (b₀ + δ)) + δ * μ.real (Icc a b) < ε

Tactic:
by
    have A : ∀ᶠ δ in 𝓝[>] (0 : ℝ), δ ∈ Ioo 0 1 := Ioo_mem_nhdsGT zero_lt_one
    have B : ∀ᶠ δ in 𝓝 0, Icc (b₀ - δ) (b₀ + δ) ⊆ Icc a b := by
      have I : Tendsto (fun δ ↦ b₀ - δ) (𝓝 0) (𝓝 (b₀ - 0)) := tendsto_const_nhds.sub tendsto_id
      have J : Tendsto (fun δ ↦ b₀ + δ) (𝓝 0) (𝓝 (b₀ + 0)) := tendsto_const_nhds.add tendsto_id
      simp only [sub_zero, add_zero] at I J
      filter_upwards [(tendsto_order.1 I).1 _ a_lt.2, (tendsto_order.1 J).2 _ lt_b.2] with δ hδ h'δ
      exact Icc_subset_Icc hδ.le h'δ.le
    have C : ∀ᶠ δ in 𝓝 0,
        (M + 1) * μ.real (Icc (b₀ - δ) (b₀ + δ)) + δ * μ.real (Icc a b) < ε := by
      suffices Tendsto
        (fun δ ↦ (M + 1) * μ.real (Icc (b₀ - δ) (b₀ + δ)) + δ * μ.real (Icc a b))
          (𝓝 0) (𝓝 ((M + 1) * (0 : ℝ≥0∞).toReal + 0 * μ.real (Icc a b))) by
        simp only [toReal_zero, mul_zero, zero_mul, add_zero] at this
        exact (tendsto_order.1 this).2 _ εpos
      apply Tendsto.add (Tendsto.mul tendsto_const_nhds _)
        (Tendsto.mul tendsto_id tendsto_const_nhds)
      exact (tendsto_toReal zero_ne_top).comp (tendsto_measure_Icc _ _)
    rcases (A.and ((B.and C).filter_mono nhdsWithin_le_nhds)).exists with ⟨δ, hδ, h'δ, h''δ⟩
    exact ⟨δ, hδ.1, hδ.2, h'δ, h''δ⟩

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.FundThmCalculus

Goal state before:
pp: case inr
E : Type u_3
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
a b : ℝ
inst✝ : CompleteSpace E
f f' : ℝ → E
hcont : ContinuousOn f [[a, b]]
hderiv : ∀ x ∈ Ioo (min a b) (max a b), HasDerivWithinAt f (f' x) (Ioi x) x
hint : IntervalIntegrable f' volume a b
hab : b ≤ a
⊢ ∫ (y : ℝ) in a..b, f' y = f b - f a

Tactic:
simp only [uIcc_of_ge, min_eq_right, max_eq_left, hab] at hcont hderiv
    rw [integral_symm, integral_eq_sub_of_hasDeriv_right_of_le hab hcont hderiv hint.symm, neg_sub]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic

Goal state before:
pp: E : Type u_5
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
b : ℝ
f : ℝ → E
μ : Measure ℝ
h_left : IntegrableOn f (Iic b) μ
h_right : IntegrableOn f (Ioi b) μ
⊢ ∫ (x : ℝ) in Iic b, f x ∂μ + ∫ (x : ℝ) in Ioi b, f x ∂μ = ∫ (x : ℝ), f x ∂μ

Tactic:
convert! (setIntegral_union (Iic_disjoint_Ioi <| Eq.le rfl) measurableSet_Ioi h_left h_right).symm
  rw [Iic_union_Ioi, Measure.restrict_univ]

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: case neg.neZeroV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ μ univ ≠ 0

Tactic:
← h

Goal state after:
case neg.neZeroV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ ν s ≠ 0
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: case neg.hV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ μ univ = ν (QuotientGroup.mk ⁻¹' univ ∩ s)

Tactic:
← h

Goal state after:
case neg.hV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ ν s = ν (QuotientGroup.mk ⁻¹' univ ∩ s)
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: case neg.neTopV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ μ univ ≠ ∞

Tactic:
← h

Goal state after:
case neg.neTopV
G : Type u_1
inst✝¹⁵ : Group G
inst✝¹⁴ : MeasurableSpace G
inst✝¹³ : TopologicalSpace G
inst✝¹² : IsTopologicalGroup G
inst✝¹¹ : BorelSpace G
inst✝¹⁰ : PolishSpace G
Γ : Subgroup G
inst✝⁹ : Γ.Normal
inst✝⁸ : T2Space (G ⧸ Γ)
inst✝⁷ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
ν : Measure G
inst✝⁶ : ν.IsMulLeftInvariant
inst✝⁵ : Countable ↥Γ
inst✝⁴ : ν.IsMulRightInvariant
inst✝³ : SigmaFinite ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : SigmaFinite μ
inst✝ : IsFiniteMeasure μ
hasFun : HasFundamentalDomain (↥Γ.op) G ν
s : Set G
h : ν s = μ univ
fund_dom_s : IsFundamentalDomain (↥Γ.op) s ν
finiteCovol : μ univ < ∞
meas_s_ne_zero : ¬ν s = 0
⊢ ν s ≠ ∞
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: G : Type u_1
inst✝¹⁴ : Group G
inst✝¹³ : MeasurableSpace G
inst✝¹² : TopologicalSpace G
inst✝¹¹ : IsTopologicalGroup G
inst✝¹⁰ : BorelSpace G
inst✝⁹ : PolishSpace G
Γ : Subgroup G
inst✝⁸ : Γ.Normal
inst✝⁷ : T2Space (G ⧸ Γ)
inst✝⁶ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
inst✝⁵ : Countable ↥Γ
ν : Measure G
inst✝⁴ : ν.IsHaarMeasure
inst✝³ : ν.IsMulRightInvariant
inst✝² : LocallyCompactSpace G
inst✝¹ : QuotientMeasureEqMeasurePreimage ν μ
i : HasFundamentalDomain (↥Γ.op) G ν
inst✝ : IsFiniteMeasure μ
K : PositiveCompacts G
K' : PositiveCompacts (G ⧸ Γ) := PositiveCompacts.map QuotientGroup.mk ⋯ ⋯ K
this : μ.IsMulLeftInvariant
⊢ (μ ↑K' • haarMeasure K').IsHaarMeasure

Tactic:
have finiteCovol : covolume Γ.op G ν ≠ ⊤ :=
    ne_top_of_lt <| QuotientMeasureEqMeasurePreimage.covolume_ne_top μ (ν := ν)

Goal state after:
G : Type u_1
inst✝¹⁴ : Group G
inst✝¹³ : MeasurableSpace G
inst✝¹² : TopologicalSpace G
inst✝¹¹ : IsTopologicalGroup G
inst✝¹⁰ : BorelSpace G
inst✝⁹ : PolishSpace G
Γ : Subgroup G
inst✝⁸ : Γ.Normal
inst✝⁷ : T2Space (G ⧸ Γ)
inst✝⁶ : SecondCountableTopology (G ⧸ Γ)
μ : Measure (G ⧸ Γ)
inst✝⁵ : Countable ↥Γ
ν : Measure G
inst✝⁴ : ν.IsHaarMeasure
inst✝³ : ν.IsMulRightInvariant
inst✝² : LocallyCompactSpace G
inst✝¹ : QuotientMeasureEqMeasurePreimage ν μ
i : HasFundamentalDomain (↥Γ.op) G ν
inst✝ : IsFiniteMeasure μ
K : PositiveCompacts G
K' : PositiveCompacts (G ⧸ Γ) := PositiveCompacts.map QuotientGroup.mk ⋯ ⋯ K
this : μ.IsMulLeftInvariant
finiteCovol : covolume (↥Γ.op) G ν ≠ ∞
⊢ (μ ↑K' • haarMeasure K').IsHaarMeasure
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: G : Type u_1
inst✝⁸ : Group G
inst✝⁷ : MeasurableSpace G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : BorelSpace G
μ : Measure G
Γ : Subgroup G
𝓕 : Set G
h𝓕 : IsFundamentalDomain (↥Γ.op) 𝓕 μ
inst✝³ : Countable ↥Γ
inst✝² : MeasurableSpace (G ⧸ Γ)
inst✝¹ : BorelSpace (G ⧸ Γ)
inst✝ : μ.IsMulRightInvariant
g : G ⧸ Γ → ℝ≥0∞
g_ae_measurable : AEMeasurable g (map QuotientGroup.mk (μ.restrict 𝓕))
hπ : Measurable QuotientGroup.mk
⊢ essSup (g ∘ QuotientGroup.mk) (μ.restrict 𝓕) = essSup (fun x ↦ g ↑x) μ

Tactic:
refine h𝓕.essSup_measure_restrict ?_

Goal state after:
G : Type u_1
inst✝⁸ : Group G
inst✝⁷ : MeasurableSpace G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : BorelSpace G
μ : Measure G
Γ : Subgroup G
𝓕 : Set G
h𝓕 : IsFundamentalDomain (↥Γ.op) 𝓕 μ
inst✝³ : Countable ↥Γ
inst✝² : MeasurableSpace (G ⧸ Γ)
inst✝¹ : BorelSpace (G ⧸ Γ)
inst✝ : μ.IsMulRightInvariant
g : G ⧸ Γ → ℝ≥0∞
g_ae_measurable : AEMeasurable g (map QuotientGroup.mk (μ.restrict 𝓕))
hπ : Measurable QuotientGroup.mk
⊢ ∀ (γ : ↥Γ.op) (x : G), (g ∘ QuotientGroup.mk) (γ • x) = (g ∘ QuotientGroup.mk) x
Module: Mathlib.MeasureTheory.Measure.Haar.Quotient

Goal state before:
pp: G : Type u_1
inst✝⁸ : Group G
inst✝⁷ : MeasurableSpace G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : BorelSpace G
μ : Measure G
Γ : Subgroup G
𝓕 : Set G
h𝓕 : IsFundamentalDomain (↥Γ.op) 𝓕 μ
inst✝³ : Countable ↥Γ
inst✝² : MeasurableSpace (G ⧸ Γ)
inst✝¹ : BorelSpace (G ⧸ Γ)
inst✝ : μ.IsMulRightInvariant
π : G → G ⧸ Γ := QuotientGroup.mk
meas_π : Measurable π
s : Set (G ⧸ Γ)
s_meas : MeasurableSet s
hs : μ (π ⁻¹' s ∩ 𝓕) = 0
γ : ↥Γ.op
⊢ γ • π ⁻¹' s = π ⁻¹' s

Tactic:
ext g

Goal state after:
G : Type u_1
inst✝⁸ : Group G
inst✝⁷ : MeasurableSpace G
inst✝⁶ : TopologicalSpace G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : BorelSpace G
μ : Measure G
Γ : Subgroup G
𝓕 : Set G
h𝓕 : IsFundamentalDomain (↥Γ.op) 𝓕 μ
inst✝³ : Countable ↥Γ
inst✝² : MeasurableSpace (G ⧸ Γ)
inst✝¹ : BorelSpace (G ⧸ Γ)
inst✝ : μ.IsMulRightInvariant
π : G → G ⧸ Γ := QuotientGroup.mk
meas_π : Measurable π
s : Set (G ⧸ Γ)
s_meas : MeasurableSet s
hs : μ (π ⁻¹' s ∩ 𝓕) = 0
γ : ↥Γ.op
g : G
⊢ g ∈ γ • π ⁻¹' s ↔ g ∈ π ⁻¹' s