Theorem: MeasureTheory.Measure.compProd_fst_condKernel
File: Mathlib/Probability/Kernel/Disintegration/Basic.lean

tactic: have h1 : const Unit (Measure.fst ρ) = fst (const Unit ρ) := by
  ext
  simp only [fst_apply, Measure.fst, const_apply]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
⊢ ρ.fst ⊗ₘ ρ.condKernel = ρ
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
⊢ ρ.fst ⊗ₘ ρ.condKernel = ρ

tactic: have h2 : prodMkLeft Unit (Measure.condKernel ρ) = condKernelUnitBorel (const Unit ρ) := by
  ext
  simp only [prodMkLeft_apply, Measure.condKernel_apply]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
⊢ ρ.fst ⊗ₘ ρ.condKernel = ρ
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
h2 : prodMkLeft Unit ρ.condKernel = condKernelUnitBorel (const Unit ρ)
⊢ ρ.fst ⊗ₘ ρ.condKernel = ρ

tactic: rw [Measure.compProd, h1, h2, compProd_fst_condKernelUnitBorel]
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
h2 : prodMkLeft Unit ρ.condKernel = condKernelUnitBorel (const Unit ρ)
⊢ ρ.fst ⊗ₘ ρ.condKernel = ρ
state_after: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
h2 : prodMkLeft Unit ρ.condKernel = condKernelUnitBorel (const Unit ρ)
⊢ (const Unit ρ) () = ρ

tactic: simp
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
h2 : prodMkLeft Unit ρ.condKernel = condKernelUnitBorel (const Unit ρ)
⊢ (const Unit ρ) () = ρ
state_after: no goals

tactic: ext
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
⊢ const Unit ρ.fst = fst (const Unit ρ)
state_after: case h.h
α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
a✝¹ : Unit
s✝ : Set α
a✝ : MeasurableSet s✝
⊢ ((const Unit ρ.fst) a✝¹) s✝ = ((fst (const Unit ρ)) a✝¹) s✝

tactic: simp only [fst_apply, Measure.fst, const_apply]
state_before: case h.h
α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
a✝¹ : Unit
s✝ : Set α
a✝ : MeasurableSet s✝
⊢ ((const Unit ρ.fst) a✝¹) s✝ = ((fst (const Unit ρ)) a✝¹) s✝
state_after: no goals

tactic: ext
state_before: α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
⊢ prodMkLeft Unit ρ.condKernel = condKernelUnitBorel (const Unit ρ)
state_after: case h.h
α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
a✝¹ : Unit × α
s✝ : Set Ω
a✝ : MeasurableSet s✝
⊢ ((prodMkLeft Unit ρ.condKernel) a✝¹) s✝ = ((condKernelUnitBorel (const Unit ρ)) a✝¹) s✝

tactic: simp only [prodMkLeft_apply, Measure.condKernel_apply]
state_before: case h.h
α : Type u_1
β : Type u_2
γ : Type u_3
Ω : Type u_4
mα : MeasurableSpace α
mβ : MeasurableSpace β
mγ : MeasurableSpace γ
inst✝⁵ : CountablyGenerated γ
inst✝⁴ : MeasurableSpace Ω
inst✝³ : StandardBorelSpace Ω
inst✝² : Nonempty Ω
ρ✝ : Measure (α × Ω)
inst✝¹ : IsFiniteMeasure ρ✝
ρ : Measure (α × Ω)
inst✝ : IsFiniteMeasure ρ
h1 : const Unit ρ.fst = fst (const Unit ρ)
a✝¹ : Unit × α
s✝ : Set Ω
a✝ : MeasurableSet s✝
⊢ ((prodMkLeft Unit ρ.condKernel) a✝¹) s✝ = ((condKernelUnitBorel (const Unit ρ)) a✝¹) s✝
state_after: no goals