mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
ν μ : Measure α
inst✝¹ : IsFiniteMeasure ν
inst✝ : ν.HaveLebesgueDecomposition μ
r : ℝ≥0∞
hr : r ≠ 0
hr_ne_top : r ≠ ∞
⊢ ν.rnDeriv (r • μ) =ᵐ[μ] r⁻¹ • ν.rnDeriv μ

Tactic:
by
  have h : ν.rnDeriv (r.toNNReal • μ) =ᵐ[μ] r.toNNReal⁻¹ • ν.rnDeriv μ := by
    refine rnDeriv_smul_right ν μ ?_
    rw [ne_eq, ENNReal.toNNReal_eq_zero_iff]
    simp [hr, hr_ne_top]
  have : (r.toNNReal)⁻¹ • rnDeriv ν μ = r⁻¹ • rnDeriv ν μ := by
    ext x
    simp only [Pi.smul_apply, ENNReal.smul_def, smul_eq_mul]
    rw [ENNReal.coe_inv, ENNReal.coe_toNNReal hr_ne_top]
    rw [ne_eq, ENNReal.toNNReal_eq_zero_iff]
    simp [hr, hr_ne_top]
  simp_rw [this, ENNReal.smul_def, ENNReal.coe_toNNReal hr_ne_top] at h
  exact h

Goal state after:
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
ν μ : Measure α
inst✝¹ : IsFiniteMeasure ν
inst✝ : ν.HaveLebesgueDecomposition μ
r : ℝ≥0
hr : r ≠ 0
⊢ (r • ν).rnDeriv (r • μ) =ᵐ[μ] ν.rnDeriv μ

Tactic:
filter_upwards [rnDeriv_smul_left ν μ r, rnDeriv_smul_right (r • ν) μ hr] with x hx1 hx2
  simp [hx1, hx2, hr]

Goal state after:
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case h₂
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
ε : ℝ≥0
εpos : ε > 0
s : Set α := {x | ¬∀ᶠ (a : Set α) in v.filterAt x, ρ a < ↑ε * μ a}
hs : s = {x | ¬∀ᶠ (a : Set α) in v.filterAt x, ρ a < ↑ε * μ a}
o : Set α
left✝ : MeasurableSet o
ρo : ρ o = 0
μo : μ oᶜ = 0
x : α
hx : x ∈ {x | ¬∀ᶠ (a : Set α) in v.filterAt x, ρ a < ↑ε * μ a} ∩ o
⊢ ∃ᶠ (a : Set α) in v.filterAt x, (↑ε • μ) a ≤ ρ a

Tactic:
simp only [mem_inter_iff, not_lt, not_eventually, mem_ofPred_eq] at hx

Goal state after:
case h₂
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
ε : ℝ≥0
εpos : ε > 0
s : Set α := {x | ¬∀ᶠ (a : Set α) in v.filterAt x, ρ a < ↑ε * μ a}
hs : s = {x | ¬∀ᶠ (a : Set α) in v.filterAt x, ρ a < ↑ε * μ a}
o : Set α
left✝ : MeasurableSet o
ρo : ρ o = 0
μo : μ oᶜ = 0
x : α
hx : (∃ᶠ (x : Set α) in v.filterAt x, ↑ε * μ x ≤ ρ x) ∧ x ∈ o
⊢ ∃ᶠ (a : Set α) in v.filterAt x, (↑ε • μ) a ≤ ρ a
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h : ¬μ ⟂ₘ ν
f : ℕ → Set α
hf₁ : ∀ (n : ℕ), MeasurableSet (f n)
hf₂ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → ((1 / (↑n + 1)) • ν) (t ∩ f n) ≤ μ (t ∩ f n)
hf₃ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → μ (t ∩ (f n)ᶜ) ≤ ((1 / (↑n + 1)) • ν) (t ∩ (f n)ᶜ)
A : Set α := ⋂ n, (f n)ᶜ
hAmeas : MeasurableSet A
hA₂ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → μ (t ∩ A) ≤ ((1 / (↑n + 1)) • ν) (t ∩ A)
hA₃ : ∀ (n : ℕ), μ A ≤ ↑(1 / (↑n + 1)) * ν A
⊢ μ A = 0

Tactic:
lift μ A to ℝ≥0 using measure_ne_top _ _ with μA

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
h : ¬μ ⟂ₘ ν
f : ℕ → Set α
hf₁ : ∀ (n : ℕ), MeasurableSet (f n)
hf₂ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → ((1 / (↑n + 1)) • ν) (t ∩ f n) ≤ μ (t ∩ f n)
hf₃ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → μ (t ∩ (f n)ᶜ) ≤ ((1 / (↑n + 1)) • ν) (t ∩ (f n)ᶜ)
A : Set α := ⋂ n, (f n)ᶜ
hAmeas : MeasurableSet A
hA₂ : ∀ (n : ℕ) (t : Set α), MeasurableSet t → μ (t ∩ A) ≤ ((1 / (↑n + 1)) • ν) (t ∩ A)
μA : ℝ≥0
hA₃ : ∀ (n : ℕ), ↑μA ≤ ↑(1 / (↑n + 1)) * ν A
⊢ ↑μA = 0
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case refine_3
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
H : ∀ (m n : ℕ), μ (toMeasurable (ρ + μ) (u m) ∩ toMeasurable (ρ + μ) (w n)) = 0
⊢ ⋃ i, toMeasurable (ρ + μ) (u i) ∩ ⋃ n, toMeasurable (ρ + μ) (w n) ⊆
    toMeasurable μ sᶜ ∪ ⋃ m, ⋃ n, toMeasurable (ρ + μ) (u m) ∩ toMeasurable (ρ + μ) (w n)

Tactic:
inter_iUnion

Goal state after:
case refine_3
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
p q : ℝ≥0
hpq : p < q
s : Set α := {x | ∃ c, Tendsto (fun a ↦ ρ a / μ a) (v.filterAt x) (𝓝 c)}
o : ℕ → Set α := spanningSets (ρ + μ)
u : ℕ → Set α := fun n ↦ s ∩ {x | v.limRatio ρ x < ↑p} ∩ o n
w : ℕ → Set α := fun n ↦ s ∩ {x | ↑q < v.limRatio ρ x} ∩ o n
H : ∀ (m n : ℕ), μ (toMeasurable (ρ + μ) (u m) ∩ toMeasurable (ρ + μ) (w n)) = 0
⊢ ⋃ i, ⋃ i_1, toMeasurable (ρ + μ) (u i) ∩ toMeasurable (ρ + μ) (w i_1) ⊆
    toMeasurable μ sᶜ ∪ ⋃ i, ⋃ i_1, toMeasurable (ρ + μ) (u i) ∩ toMeasurable (ρ + μ) (w i_1)
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: case inr.inl
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
a : α
⊢ variationOnFromTo f s a a = -variationOnFromTo f s a a

pp: case inr.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
a b : α
ba : b < a
⊢ variationOnFromTo f s a b = -variationOnFromTo f s b a

Tactic:
· simp only [variationOnFromTo.self, neg_zero]

Goal state after:
case inr.inr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
a b : α
ba : b < a
⊢ variationOnFromTo f s a b = -variationOnFromTo f s b a
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a b : α
ha : a ∈ s
hb : b ∈ s
ab : a ≤ b
⊢ eVariationOn f (s ∩ Icc a b) = 0 ∨ eVariationOn f (s ∩ Icc a b) = ∞ ↔
    ∀ ⦃x : α⦄, x ∈ s ∩ Icc a b → ∀ ⦃y : α⦄, y ∈ s ∩ Icc a b → edist (f x) (f y) = 0

Tactic:
or_iff_left (hf a b ha hb),

Goal state after:
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
hf : LocallyBoundedVariationOn f s
a b : α
ha : a ∈ s
hb : b ∈ s
ab : a ≤ b
⊢ eVariationOn f (s ∩ Icc a b) = 0 ↔ ∀ ⦃x : α⦄, x ∈ s ∩ Icc a b → ∀ ⦃y : α⦄, y ∈ s ∩ Icc a b → edist (f x) (f y) = 0
Module: Mathlib.Topology.EMetricSpace.VariationOnFromTo

Goal state before:
pp: α : Type u_1
inst✝³ : LinearOrder α
s : Set α
E : Type u_3
inst✝² : PseudoMetricSpace E
inst✝¹ : TopologicalSpace α
inst✝ : OrderTopology α
f : α → E
l : E
a b : α
ha : a ∈ s
hb : b ∈ s
hf : LocallyBoundedVariationOn f s
h'f : Tendsto f (𝓝[s ∩ Iio b] b) (𝓝 l)
⊢ Tendsto (fun x ↦ (eVariationOn f (s ∩ Icc x b)).toReal) (𝓝[s ∩ Iio b] b) (𝓝 (edist (f b) l).toReal)

Tactic:
exact (ENNReal.tendsto_toReal (by simp)).comp (hf.tendsto_eVariationOn_Icc_left h'f hb)

Goal state after:
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

Goal state before:
pp: case mpr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
h : ∀ x ∈ s, ∀ y ∈ s, edist (f x) (f y) = 0
⊢ ⨆ p, ∑ i ∈ Finset.range p.1, edist (f (↑p.2 (i + 1))) (f (↑p.2 i)) = 0

Tactic:
rw [ENNReal.iSup_eq_zero]

Goal state after:
case mpr
α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s : Set α
h : ∀ x ∈ s, ∀ y ∈ s, edist (f x) (f y) = 0
⊢ ∀ (i : ℕ × { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ s }),
    ∑ i_1 ∈ Finset.range i.1, edist (f (↑i.2 (i_1 + 1))) (f (↑i.2 i_1)) = 0
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
hρ : ρ ≪ μ
s : Set α
hs : MeasurableSet s
t : ℝ≥0
ht : 1 < t
t_ne_zero' : t ≠ 0
t_ne_zero : ↑t ≠ 0
ν : Measure α := μ.withDensity (v.limRatioMeas hρ)
f : α → ℝ≥0∞ := v.limRatioMeas hρ
f_meas : Measurable f
A : ν (s ∩ f ⁻¹' {0}) ≤ (↑t ^ 2 • ρ) (s ∩ f ⁻¹' {0})
B : ν (s ∩ f ⁻¹' {∞}) ≤ (↑t ^ 2 • ρ) (s ∩ f ⁻¹' {∞})
n : ℤ
I : Set ℝ≥0∞ := Ico (↑t ^ n) (↑t ^ (n + 1))
M : MeasurableSet (s ∩ f ⁻¹' I)
⊢ ∫⁻ (a : α) in s ∩ f ⁻¹' Ico (↑t ^ n) (↑t ^ (n + 1)), v.limRatioMeas hρ a ∂μ ≤
    (↑t ^ 2 • ρ) (s ∩ f ⁻¹' Ico (↑t ^ n) (↑t ^ (n + 1)))

Tactic:
calc
      (∫⁻ x in s ∩ f ⁻¹' I, f x ∂μ) ≤ ∫⁻ _ in s ∩ f ⁻¹' I, (t : ℝ≥0∞) ^ (n + 1) ∂μ :=
        lintegral_mono_ae ((ae_restrict_iff' M).2 (Eventually.of_forall fun x hx => hx.2.2.le))
      _ = (t : ℝ≥0∞) ^ (n + 1) * μ (s ∩ f ⁻¹' I) := by
        simp only [lintegral_const, MeasurableSet.univ, Measure.restrict_apply, univ_inter]
      _ = (t : ℝ≥0∞) ^ (2 : ℤ) * ((t : ℝ≥0∞) ^ (n - 1) * μ (s ∩ f ⁻¹' I)) := by
        rw [← mul_assoc, ← ENNReal.zpow_add t_ne_zero ENNReal.coe_ne_top]
        congr 2
        abel
      _ ≤ (t : ℝ≥0∞) ^ (2 : ℤ) * ρ (s ∩ f ⁻¹' I) := by
        gcongr
        rw [← ENNReal.coe_zpow (zero_lt_one.trans ht).ne']
        apply v.mul_measure_le_of_subset_lt_limRatioMeas hρ
        intro x hx
        apply lt_of_lt_of_le _ hx.2.1
        rw [← ENNReal.coe_zpow (zero_lt_one.trans ht).ne', ENNReal.coe_lt_coe, sub_eq_add_neg,
          zpow_add₀ t_ne_zero']
        conv_rhs => rw [← mul_one (t ^ n)]
        gcongr
        rw [zpow_neg_one]
        exact inv_lt_one_of_one_lt₀ ht

Goal state after:
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
t : Measure α := μ.withDensity (ρ.rnDeriv μ)
eq_add : ρ = ρ.singularPart μ + t
A : ∀ᵐ (x : α) ∂μ, Tendsto (fun a ↦ (ρ.singularPart μ) a / μ a) (v.filterAt x) (𝓝 0)
B : ∀ᵐ (x : α) ∂μ, t.rnDeriv μ x = ρ.rnDeriv μ x
C : ∀ᵐ (x : α) ∂μ, Tendsto (fun a ↦ t a / μ a) (v.filterAt x) (𝓝 (t.rnDeriv μ x))
a✝ : α
⊢ Tendsto (fun a ↦ (ρ.singularPart μ) a / μ a) (v.filterAt a✝) (𝓝 0) →
    t.rnDeriv μ a✝ = ρ.rnDeriv μ a✝ →
      Tendsto (fun a ↦ t a / μ a) (v.filterAt a✝) (𝓝 (t.rnDeriv μ a✝)) →
        Tendsto (fun a ↦ ρ a / μ a) (v.filterAt a✝) (𝓝 (ρ.rnDeriv μ a✝))

Tactic:
Ax

Goal state after:
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
inst✝³ : SecondCountableTopology α
inst✝² : BorelSpace α
inst✝¹ : IsLocallyFiniteMeasure μ
ρ : Measure α
inst✝ : IsLocallyFiniteMeasure ρ
t : Measure α := μ.withDensity (ρ.rnDeriv μ)
eq_add : ρ = ρ.singularPart μ + t
A : ∀ᵐ (x : α) ∂μ, Tendsto (fun a ↦ (ρ.singularPart μ) a / μ a) (v.filterAt x) (𝓝 0)
B : ∀ᵐ (x : α) ∂μ, t.rnDeriv μ x = ρ.rnDeriv μ x
C : ∀ᵐ (x : α) ∂μ, Tendsto (fun a ↦ t a / μ a) (v.filterAt x) (𝓝 (t.rnDeriv μ x))
a✝ : α
Ax : Tendsto (fun a ↦ (ρ.singularPart μ) a / μ a) (v.filterAt a✝) (𝓝 0)
⊢ t.rnDeriv μ a✝ = ρ.rnDeriv μ a✝ →
    Tendsto (fun a ↦ t a / μ a) (v.filterAt a✝) (𝓝 (t.rnDeriv μ a✝)) →
      Tendsto (fun a ↦ ρ a / μ a) (v.filterAt a✝) (𝓝 (ρ.rnDeriv μ a✝))
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : SecondCountableTopology α
inst✝¹ : BorelSpace α
inst✝ : IsLocallyFiniteMeasure μ
f : α → E
hf : Integrable f μ
h'f : StronglyMeasurable f
A : μ.FiniteSpanningSetsIn {K | IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] K} :=
  μ.finiteSpanningSetsInOpen'
t : Set E
t_count : t.Countable
ht : range f ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] t
main :
  ∀ᵐ (x : α) ∂μ,
    ∀ (n : ℕ),
      ∀ c ∈ t,
        Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - (A.set n).indicator (fun x ↦ c) y‖ₑ ∂μ) / μ a) (v.filterAt x)
          (𝓝 ‖f x - (A.set n).indicator (fun x ↦ c) x‖ₑ)
x : α
hx :
  ∀ (n : ℕ),
    ∀ c ∈ t,
      Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - (A.set n).indicator (fun x ↦ c) y‖ₑ ∂μ) / μ a) (v.filterAt x)
        (𝓝 ‖f x - (A.set n).indicator (fun x ↦ c) x‖ₑ)
h'x : ∀ᶠ (a : Set α) in v.filterAt x, 0 < μ a
M : ∀ c ∈ t, Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 ‖f x - c‖ₑ)
ε : ℝ≥0∞
εpos : ε > 0
c : E
ct : c ∈ t
xc : ‖f x - c‖ₑ < ε / 2
a : Set α
ha : (∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ) / μ a < ε / 2
h'a : 0 < μ a
h''a : μ a < ∞
⊢ ε / 2 * μ a + ε / 2 * μ a = ε * μ a

Tactic:
← add_mul,

Goal state after:
α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : SecondCountableTopology α
inst✝¹ : BorelSpace α
inst✝ : IsLocallyFiniteMeasure μ
f : α → E
hf : Integrable f μ
h'f : StronglyMeasurable f
A : μ.FiniteSpanningSetsIn {K | IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] K} :=
  μ.finiteSpanningSetsInOpen'
t : Set E
t_count : t.Countable
ht : range f ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] t
main :
  ∀ᵐ (x : α) ∂μ,
    ∀ (n : ℕ),
      ∀ c ∈ t,
        Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - (A.set n).indicator (fun x ↦ c) y‖ₑ ∂μ) / μ a) (v.filterAt x)
          (𝓝 ‖f x - (A.set n).indicator (fun x ↦ c) x‖ₑ)
x : α
hx :
  ∀ (n : ℕ),
    ∀ c ∈ t,
      Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - (A.set n).indicator (fun x ↦ c) y‖ₑ ∂μ) / μ a) (v.filterAt x)
        (𝓝 ‖f x - (A.set n).indicator (fun x ↦ c) x‖ₑ)
h'x : ∀ᶠ (a : Set α) in v.filterAt x, 0 < μ a
M : ∀ c ∈ t, Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 ‖f x - c‖ₑ)
ε : ℝ≥0∞
εpos : ε > 0
c : E
ct : c ∈ t
xc : ‖f x - c‖ₑ < ε / 2
a : Set α
ha : (∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ) / μ a < ε / 2
h'a : 0 < μ a
h''a : μ a < ∞
⊢ (ε / 2 + ε / 2) * μ a = ε * μ a
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: α : Type u_1
inst✝⁴ : PseudoMetricSpace α
m0 : MeasurableSpace α
μ : Measure α
v : VitaliFamily μ
E : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : SecondCountableTopology α
inst✝¹ : BorelSpace α
inst✝ : IsLocallyFiniteMeasure μ
f : α → E
hf : LocallyIntegrable f μ
x : α
hx : Tendsto (fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
this : Tendsto (ENNReal.toReal ∘ fun a ↦ (∫⁻ (y : α) in a, ‖f y - f x‖ₑ ∂μ) / μ a) (v.filterAt x) (𝓝 0)
a : Set α
h'a : μ a < ∞
h''a : IntegrableOn f a μ
A : IntegrableOn (fun y ↦ ↑‖f y - f x‖₊) a μ
⊢ 0 ≤ ∫ (a : α) in a, ↑‖f a - f x‖₊ ∂μ

Tactic:
by positivity

Goal state after:
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

Goal state before:
pp: α : Type u_1
inst✝³ : LinearOrder α
E : Type u_2
inst✝² : PseudoEMetricSpace E
inst✝¹ : CompleteSpace E
inst✝ : DenselyOrdered α
f : α → E
a : α
hf : BoundedVariationOn f univ
⊢ eVariationOn (f ∘ ⇑ofDual) (⇑ofDual ⁻¹' Ici a) =
    eVariationOn (f ∘ ⇑ofDual) (⇑ofDual ⁻¹' Ioi a) + edist (f a) (Function.rightLim f a)

Tactic:
exact hf.ofDual.eVariationOn_Iic_eq_Iio_add_edist (a := toDual a)

Goal state after:
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unital

Goal state before:
pp: R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : CommSemiring R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : TopologicalSpace A
inst✝³ : Ring A
inst✝² : StarRing A
inst✝¹ : Algebra R A
instCFC : ContinuousFunctionalCalculus R A p
inst✝ : UniqueHom R A
g f : R → R
a : A
ha : p a
hg : ContinuousOn g (f '' spectrum R a)
hf : ContinuousOn f (spectrum R a)
this : ContinuousOn (g ∘ f) (spectrum R a)
sp_eq : spectrum R ((cfcHom ⋯) { toFun := (spectrum R a).domRestrict f, continuous_toFun := ⋯ }) = f '' spectrum R a
x : ↑(spectrum R a)
⊢ (spectrum R a).domRestrict f x ∈
    spectrum R ((cfcHom ⋯) { toFun := (spectrum R a).domRestrict f, continuous_toFun := ⋯ })

Tactic:
rw [sp_eq]

Goal state after:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁹ : CommSemiring R
inst✝⁸ : StarRing R
inst✝⁷ : MetricSpace R
inst✝⁶ : IsTopologicalSemiring R
inst✝⁵ : ContinuousStar R
inst✝⁴ : TopologicalSpace A
inst✝³ : Ring A
inst✝² : StarRing A
inst✝¹ : Algebra R A
instCFC : ContinuousFunctionalCalculus R A p
inst✝ : UniqueHom R A
g f : R → R
a : A
ha : p a
hg : ContinuousOn g (f '' spectrum R a)
hf : ContinuousOn f (spectrum R a)
this : ContinuousOn (g ∘ f) (spectrum R a)
sp_eq : spectrum R ((cfcHom ⋯) { toFun := (spectrum R a).domRestrict f, continuous_toFun := ⋯ }) = f '' spectrum R a
x : ↑(spectrum R a)
⊢ (spectrum R a).domRestrict f x ∈ f '' spectrum R a
Module: Mathlib.RingTheory.Polynomial.Bernstein

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
n ν : ℕ
⊢ Polynomial.derivative (↑((n + 1).choose (ν + 1)) * X ^ (ν + 1) * (1 - X) ^ (n + 1 - (ν + 1))) =
    (↑n + 1) * (bernsteinPolynomial R n ν - bernsteinPolynomial R n (ν + 1))

Tactic:
suffices ((n + 1).choose (ν + 1) : R[X]) * ((↑(ν + 1 : ℕ) : R[X]) * X ^ ν) * (1 - X) ^ (n - ν) -
      ((n + 1).choose (ν + 1) : R[X]) * X ^ (ν + 1) * ((↑(n - ν) : R[X]) * (1 - X) ^ (n - ν - 1)) =
      (↑(n + 1) : R[X]) * ((n.choose ν : R[X]) * X ^ ν * (1 - X) ^ (n - ν) -
        (n.choose (ν + 1) : R[X]) * X ^ (ν + 1) * (1 - X) ^ (n - (ν + 1))) by
    simpa [Polynomial.derivative_pow, ← sub_eq_add_neg, Nat.succ_sub_succ_eq_sub,
      Polynomial.derivative_mul, Polynomial.derivative_natCast, zero_mul,
      Nat.cast_add, algebraMap.coe_one, Polynomial.derivative_X, mul_one, zero_add,
      Polynomial.derivative_sub, Polynomial.derivative_one, zero_sub, mul_neg, Nat.sub_zero,
      bernsteinPolynomial, map_add, map_natCast, Nat.cast_one]

Goal state after:
R : Type u_1
inst✝ : CommRing R
n ν : ℕ
⊢ ↑((n + 1).choose (ν + 1)) * (↑(ν + 1) * X ^ ν) * (1 - X) ^ (n - ν) -
      ↑((n + 1).choose (ν + 1)) * X ^ (ν + 1) * (↑(n - ν) * (1 - X) ^ (n - ν - 1)) =
    ↑(n + 1) * (↑(n.choose ν) * X ^ ν * (1 - X) ^ (n - ν) - ↑(n.choose (ν + 1)) * X ^ (ν + 1) * (1 - X) ^ (n - (ν + 1)))
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.NonUnital

Goal state before:
pp: R : Type u_1
A : Type u_2
p : A → Prop
inst✝¹² : CommSemiring R
inst✝¹¹ : Nontrivial R
inst✝¹⁰ : StarRing R
inst✝⁹ : MetricSpace R
inst✝⁸ : IsTopologicalSemiring R
inst✝⁷ : ContinuousStar R
inst✝⁶ : NonUnitalRing A
inst✝⁵ : StarRing A
inst✝⁴ : TopologicalSpace A
inst✝³ : Module R A
inst✝² : IsScalarTower R A A
inst✝¹ : SMulCommClass R A A
instCFCₙ : NonUnitalContinuousFunctionalCalculus R A p
inst✝ : UniqueHom R A
g f : R → R
a : A
hg : ContinuousOn g (f '' σₙ R a)
hg0 : g 0 = 0
hf : ContinuousOn f (σₙ R a)
hf0 : f 0 = 0
ha : p a
this : ContinuousOn (g ∘ f) (σₙ R a)
sp_eq : σₙ R ((cfcₙHom ⋯) { toFun := (σₙ R a).domRestrict f, continuous_toFun := ⋯, map_zero' := hf0 }) = f '' σₙ R a
x : ↑(σₙ R a)
⊢ (σₙ R a).domRestrict f x ∈
    σₙ R ((cfcₙHom ⋯) { toFun := (σₙ R a).domRestrict f, continuous_toFun := ⋯, map_zero' := ⋯ })

Tactic:
rw [sp_eq]

Goal state after:
R : Type u_1
A : Type u_2
p : A → Prop
inst✝¹² : CommSemiring R
inst✝¹¹ : Nontrivial R
inst✝¹⁰ : StarRing R
inst✝⁹ : MetricSpace R
inst✝⁸ : IsTopologicalSemiring R
inst✝⁷ : ContinuousStar R
inst✝⁶ : NonUnitalRing A
inst✝⁵ : StarRing A
inst✝⁴ : TopologicalSpace A
inst✝³ : Module R A
inst✝² : IsScalarTower R A A
inst✝¹ : SMulCommClass R A A
instCFCₙ : NonUnitalContinuousFunctionalCalculus R A p
inst✝ : UniqueHom R A
g f : R → R
a : A
hg : ContinuousOn g (f '' σₙ R a)
hg0 : g 0 = 0
hf : ContinuousOn f (σₙ R a)
hf0 : f 0 = 0
ha : p a
this : ContinuousOn (g ∘ f) (σₙ R a)
sp_eq : σₙ R ((cfcₙHom ⋯) { toFun := (σₙ R a).domRestrict f, continuous_toFun := ⋯, map_zero' := hf0 }) = f '' σₙ R a
x : ↑(σₙ R a)
⊢ (σₙ R a).domRestrict f x ∈ f '' σₙ R a
Module: Mathlib.Topology.ContinuousMap.Polynomial

Goal state before:
pp: case mp.refine_2.convert_2
a b : ℝ
h : a < b
f : C(↑(Set.Icc a b), ℝ)
p : ℝ[X]
w : ∀ (x : ↑I), Polynomial.eval (↑x) p = f ((iccHomeoI a b h).symm x)
q : ℝ[X] := p.comp ((b - a)⁻¹ • X + Polynomial.C (-a * (b - a)⁻¹))
x : ↑(Set.Icc a b)
⊢ ↑x * (b - a)⁻¹ + -a * (b - a)⁻¹ ∈ I

Tactic:
← add_mul,

Goal state after:
case mp.refine_2.convert_2
a b : ℝ
h : a < b
f : C(↑(Set.Icc a b), ℝ)
p : ℝ[X]
w : ∀ (x : ↑I), Polynomial.eval (↑x) p = f ((iccHomeoI a b h).symm x)
q : ℝ[X] := p.comp ((b - a)⁻¹ • X + Polynomial.C (-a * (b - a)⁻¹))
x : ↑(Set.Icc a b)
⊢ (↑x + -a) * (b - a)⁻¹ ∈ I
Module: Mathlib.Topology.ContinuousMap.Polynomial

Goal state before:
pp: case refine_1
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : IsTopologicalSemiring R
s : Set R
p : R[X]
r : R
⊢ (toContinuousMapOnAlgHom s) ((algebraMap R R[X]) r) ∈ R[(toContinuousMapOnAlgHom s) X]

Tactic:
AlgHomClass.commutes

Goal state after:
case refine_1
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : IsTopologicalSemiring R
s : Set R
p : R[X]
r : R
⊢ (algebraMap R C(↑s, R)) r ∈ R[(toContinuousMapOnAlgHom s) X]
Module: Mathlib.Analysis.SpecialFunctions.Bernstein

Goal state before:
pp: E : Type u_1
inst✝⁵ : AddCommGroup E
inst✝⁴ : TopologicalSpace E
inst✝³ : IsTopologicalAddGroup E
inst✝² : Module ℝ E
inst✝¹ : ContinuousSMul ℝ E
inst✝ : LocallyConvexSpace ℝ E
f : C(↑I, E)
this✝¹ : UniformSpace E := IsTopologicalAddGroup.rightUniformSpace E
this✝ : IsUniformAddGroup E
U : Set E
hU₀ : U ∈ 𝓝 0
hUc : Convex ℝ U
C : ℝ
hC : ∀ (x y : ↑I), gauge U (f x - f y) ≤ C
hC₀ : 0 ≤ C
this : ∀ i ∈ 𝓝 0, ∃ j, 0 < j ∧ ∀ (x y : ↑I), (x, y) ∈ {p | dist p.1 p.2 < j} → (f x, f y) ∈ {x | x.1 - x.2 ∈ id i}
⊢ 0 < 1 / 2

Tactic:
by positivity

Goal state after:
Module: Mathlib.Topology.ContinuousMap.StoneWeierstrass

Goal state before:
pp: X : Type u_1
inst✝¹ : TopologicalSpace X
inst✝ : CompactSpace X
A : Subalgebra ℝ C(X, ℝ)
f g : ↥A
⊢ ↑f ⊓ ↑g ∈ A.topologicalClosure

Tactic:
rw [inf_eq_half_smul_add_sub_abs_sub' ℝ]

Goal state after:
X : Type u_1
inst✝¹ : TopologicalSpace X
inst✝ : CompactSpace X
A : Subalgebra ℝ C(X, ℝ)
f g : ↥A
⊢ 2⁻¹ • (↑f + ↑g - |↑g - ↑f|) ∈ A.topologicalClosure
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unique

Goal state before:
pp: X : Type u_1
inst✝³ : TopologicalSpace X
A : Type u_2
inst✝² : Ring A
inst✝¹ : StarRing A
inst✝ : Algebra ℝ A
φ : C(X, ℝ≥0) →⋆ₐ[ℝ≥0] A
f : C(X, ℝ≥0)
⊢ φ f - φ 0 = φ f

Tactic:
map_zero,

Goal state after:
X : Type u_1
inst✝³ : TopologicalSpace X
A : Type u_2
inst✝² : Ring A
inst✝¹ : StarRing A
inst✝ : Algebra ℝ A
φ : C(X, ℝ≥0) →⋆ₐ[ℝ≥0] A
f : C(X, ℝ≥0)
⊢ φ f - 0 = φ f
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unique

Goal state before:
pp: X : Type u_1
inst✝⁴ : TopologicalSpace X
inst✝³ : Zero X
A : Type u_2
inst✝² : NonUnitalRing A
inst✝¹ : StarRing A
inst✝ : Module ℝ A
φ : C(X, ℝ≥0)₀ →⋆ₙₐ[ℝ≥0] A
f : C(X, ℝ≥0)₀
⊢ φ f - φ 0 = φ f

Tactic:
map_zero,

Goal state after:
X : Type u_1
inst✝⁴ : TopologicalSpace X
inst✝³ : Zero X
A : Type u_2
inst✝² : NonUnitalRing A
inst✝¹ : StarRing A
inst✝ : Module ℝ A
φ : C(X, ℝ≥0)₀ →⋆ₙₐ[ℝ≥0] A
f : C(X, ℝ≥0)₀
⊢ φ f - 0 = φ f
Module: Mathlib.Topology.ContinuousMap.StoneWeierstrass

Goal state before:
pp: case add
𝕜 : Type u_1
inst✝ : RCLike 𝕜
s : Set 𝕜
p : C(↑s, 𝕜) → Prop
const : ∀ (r : 𝕜), p (ContinuousMap.const (↑s) r)
id : p (restrict s (ContinuousMap.id 𝕜))
star_id : p (star (restrict s (ContinuousMap.id 𝕜)))
add : ∀ (f g : C(↑s, 𝕜)), p f → p g → p (f + g)
mul : ∀ (f g : C(↑s, 𝕜)), p f → p g → p (f * g)
closure : (∀ f ∈ (polynomialFunctions s).starClosure, p f) → ∀ (f : C(↑s, 𝕜)), p f
f✝ f x✝ y✝ : C(↑s, 𝕜)
hx✝ : x✝ ∈ Algebra.adjoin 𝕜 ({(toContinuousMapOnAlgHom s) X} ∪ star {(toContinuousMapOnAlgHom s) X})
hy✝ : y✝ ∈ Algebra.adjoin 𝕜 ({(toContinuousMapOnAlgHom s) X} ∪ star {(toContinuousMapOnAlgHom s) X})
hf : p x✝
hg : p y✝
⊢ p (x✝ + y✝)

Tactic:
| add _ _ _ _ hf hg =>

Goal state after: