Theorem: ProbabilityTheory.kernel.setLIntegral_rnDerivAux
File: Mathlib/Probability/Kernel/RadonNikodym.lean

tactic: have h_le : κ ≤ κ + η := le_add_of_nonneg_right bot_le
state_before: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (rnDerivAux κ (κ + η) a x) ∂(κ + η) a = (κ a) s
state_after: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (rnDerivAux κ (κ + η) a x) ∂(κ + η) a = (κ a) s

tactic: simp_rw [rnDerivAux]
state_before: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (rnDerivAux κ (κ + η) a x) ∂(κ + η) a = (κ a) s
state_after: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
⊢ ∫⁻ (x : γ) in s,
      ENNReal.ofReal
        (if hα : Countable α then ((∂κ a/∂(κ + η) a) x).toReal
        else density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a =
    (κ a) s

tactic: split_ifs with hα
state_before: α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
⊢ ∫⁻ (x : γ) in s,
      ENNReal.ofReal
        (if hα : Countable α then ((∂κ a/∂(κ + η) a) x).toReal
        else density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a =
    (κ a) s
state_after: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a = (κ a) s

case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a = (κ a) s

tactic: have h_ac : κ a ≪ (κ + η) a := Measure.absolutelyContinuous_of_le (h_le a)
state_before: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a = (κ a) s
state_after: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a = (κ a) s

tactic: rw [← Measure.setLIntegral_rnDeriv h_ac]
state_before: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a = (κ a) s
state_after: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a =
    ∫⁻ (x : γ) in s, (∂κ a/∂(κ + η) a) x ∂(κ + η) a

tactic: refine setLIntegral_congr_fun hs ?_
state_before: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal ∂(κ + η) a =
    ∫⁻ (x : γ) in s, (∂κ a/∂(κ + η) a) x ∂(κ + η) a
state_after: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∀ᵐ (x : γ) ∂(κ + η) a, x ∈ s → ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal = (∂κ a/∂(κ + η) a) x

tactic: filter_upwards [Measure.rnDeriv_lt_top (κ a) ((κ + η) a)] with x hx_lt _
state_before: case pos
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
⊢ ∀ᵐ (x : γ) ∂(κ + η) a, x ∈ s → ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal = (∂κ a/∂(κ + η) a) x
state_after: case h
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
x : γ
hx_lt : (∂κ a/∂(κ + η) a) x < ⊤
a✝ : x ∈ s
⊢ ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal = (∂κ a/∂(κ + η) a) x

tactic: rw [ENNReal.ofReal_toReal hx_lt.ne]
state_before: case h
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : Countable α
h_ac : κ a ≪ (κ + η) a
x : γ
hx_lt : (∂κ a/∂(κ + η) a) x < ⊤
a✝ : x ∈ s
⊢ ENNReal.ofReal ((∂κ a/∂(κ + η) a) x).toReal = (∂κ a/∂(κ + η) a) x
state_after: no goals

tactic: have := hαγ.countableOrCountablyGenerated.resolve_left hα
state_before: case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a = (κ a) s
state_after: case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a = (κ a) s

tactic: rw [setLIntegral_density ((fst_map_id_prod _ measurable_const).trans_le h_le) _
  MeasurableSet.univ hs, map_apply' _ _ _ (hs.prod MeasurableSet.univ)]
state_before: case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
⊢ ∫⁻ (x : γ) in s, ENNReal.ofReal (density (map κ (fun a => (a, ())) ⋯) (κ + η) a x univ) ∂(κ + η) a = (κ a) s
state_after: case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
⊢ (κ a) ((fun a => (a, ())) ⁻¹' s ×ˢ univ) = (κ a) s

tactic: congr with x
state_before: case neg
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
⊢ (κ a) ((fun a => (a, ())) ⁻¹' s ×ˢ univ) = (κ a) s
state_after: case neg.h.e_6.h.h
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
x : γ
⊢ x ∈ (fun a => (a, ())) ⁻¹' s ×ˢ univ ↔ x ∈ s

tactic: simp
state_before: case neg.h.e_6.h.h
α : Type u_1
γ : Type u_2
mα : MeasurableSpace α
mγ : MeasurableSpace γ
κ✝ η✝ : ↥(kernel α γ)
hαγ : MeasurableSpace.CountableOrCountablyGenerated α γ
κ η : ↥(kernel α γ)
inst✝¹ : IsFiniteKernel κ
inst✝ : IsFiniteKernel η
a : α
s : Set γ
hs : MeasurableSet s
h_le : κ ≤ κ + η
hα : ¬Countable α
this : MeasurableSpace.CountablyGenerated γ
x : γ
⊢ x ∈ (fun a => (a, ())) ⁻¹' s ×ˢ univ ↔ x ∈ s
state_after: no goals