Theorem: VitaliFamily.ae_tendsto_lintegral_div'
File: Mathlib/MeasureTheory/Covering/Differentiation.lean

Proof steps:
state_before: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
⊢ ∀ᵐ (x : α) ∂μ, Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
state_after: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
⊢ ∀ᵐ (x : α) ∂μ, Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
tactic: let ρ := μ.withDensity f
state_before: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
⊢ ∀ᵐ (x : α) ∂μ, Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
state_after: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
⊢ ∀ᵐ (x : α) ∂μ, Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
tactic: have : IsFiniteMeasure ρ := isFiniteMeasure_withDensity h'f
state_before: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
⊢ ∀ᵐ (x : α) ∂μ, Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
state_after: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
tactic: filter_upwards [ae_tendsto_rnDeriv v ρ, rnDeriv_withDensity μ hf] with x hx h'x
state_before: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 (f x))
state_after: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 ((μ.withDensity f).rnDeriv μ x))
tactic: rw [← h'x]
state_before: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ Tendsto (fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a) (v.filterAt x) (𝓝 ((μ.withDensity f).rnDeriv μ x))
state_after: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ (fun a => ρ a / μ a) =ᶠ[v.filterAt x] fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a
tactic: apply hx.congr' _
state_before: α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
⊢ (fun a => ρ a / μ a) =ᶠ[v.filterAt x] fun a => (∫⁻ (y : α) in a, f y ∂μ) / μ a
state_after: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
a : Set α
ha : MeasurableSet a
⊢ ρ a / μ a = (∫⁻ (y : α) in a, f y ∂μ) / μ a
tactic: filter_upwards [v.eventually_filterAt_measurableSet x] with a ha
state_before: case h
α : Type u_1
inst✝⁵ : MetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ✝ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ✝
f : α → ℝ≥0∞
hf : Measurable f
h'f : ∫⁻ (y : α), f y ∂μ ≠ ⊤
ρ : Measure α := μ.withDensity f
this : IsFiniteMeasure ρ
x : α
hx : Tendsto (fun a => ρ a / μ a) (v.filterAt x) (𝓝 (ρ.rnDeriv μ x))
h'x : (μ.withDensity f).rnDeriv μ x = f x
a : Set α
ha : MeasurableSet a
⊢ ρ a / μ a = (∫⁻ (y : α) in a, f y ∂μ) / μ a
state_after: no goals
tactic: rw [← withDensity_apply f ha]