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

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
⊢ (ν.withDensity f) (A ∩ (S ∩ T)ᶜ) = 0

Tactic:
refine withDensity_absolutelyContinuous ν _ ?_

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
⊢ ν (A ∩ (S ∩ T)ᶜ) = 0
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf✝ : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
hf : (ν.withDensity f) (A ∩ (S ∩ T)ᶜ) = 0
⊢ (ν.withDensity (μ.rnDeriv ν)) (A ∩ (S ∩ T)ᶜ) = 0

Tactic:
refine withDensity_absolutelyContinuous ν _ ?_

Goal state after:
α : Type u_1
m : MeasurableSpace α
μ ν s : Measure α
f : α → ℝ≥0∞
hf✝ : Measurable f
hadd : μ.singularPart ν + ν.withDensity (μ.rnDeriv ν) = s + ν.withDensity f
this : μ.HaveLebesgueDecomposition ν
hmeas : Measurable (μ.rnDeriv ν)
hadd' : μ = μ.singularPart ν + ν.withDensity (μ.rnDeriv ν)
S : Set α
hS₁ : MeasurableSet S
hS₂ : s S = 0
hS₃ : ν Sᶜ = 0
T : Set α
hT₁ : MeasurableSet T
hT₂ : (μ.singularPart ν) T = 0
hT₃ : ν Tᶜ = 0
hνinter : ν (S ∩ T)ᶜ = 0
A : Set α
hA : MeasurableSet A
hf : (ν.withDensity f) (A ∩ (S ∩ T)ᶜ) = 0
⊢ ν (A ∩ (S ∩ T)ᶜ) = 0
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: case pos.refine_2
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
r : ℝ≥0
hr : r ≠ 0
hl : μ.HaveLebesgueDecomposition ν
⊢ μ = μ.singularPart ν + (r • ν).withDensity (r⁻¹ • μ.rnDeriv ν)

Tactic:
· rw [ENNReal.smul_def r, withDensity_smul_measure, ← withDensity_smul]
      swap; · exact (measurable_rnDeriv _ _).const_smul _
      convert! haveLebesgueDecomposition_add μ ν
      ext x
      simp only [Pi.smul_apply]
      rw [← ENNReal.smul_def, smul_inv_smul₀ hr]

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
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
⊢ μ (s ∩ o) = 1 * μ (s ∩ o)

Tactic:
one_mul

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
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
⊢ μ (s ∩ o) = μ (s ∩ o)
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case hc
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
w : Set ℝ≥0∞
w_count : w.Countable
w_dense : Dense w
left✝ : 0 ∉ w
w_top : ∞ ∉ w
I : ∀ x ∈ w, x ≠ ∞
c : ℝ≥0
hc : ↑c ∈ w
d : ℝ≥0
hd : ↑d ∈ w
hcd : ↑c < ↑d
⊢ ∀
    x ∈
      {x |
          (fun x ↦ ¬((∃ᶠ (a : Set α) in v.filterAt x, ρ a / μ a < ↑c) ∧ ∃ᶠ (a : Set α) in v.filterAt x, ↑d < ρ a / μ a))
            x}ᶜ,
    ∃ᶠ (a : Set α) in v.filterAt x, ρ a ≤ ↑c * μ a

Tactic:
simp only [and_imp, exists_prop, not_frequently, not_and, not_lt, not_le, not_eventually,
        mem_ofPred_eq, mem_compl_iff, not_forall]

Goal state after:
case hc
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
w : Set ℝ≥0∞
w_count : w.Countable
w_dense : Dense w
left✝ : 0 ∉ w
w_top : ∞ ∉ w
I : ∀ x ∈ w, x ≠ ∞
c : ℝ≥0
hc : ↑c ∈ w
d : ℝ≥0
hd : ↑d ∈ w
hcd : ↑c < ↑d
⊢ ∀ (x : α),
    (∃ᶠ (a : Set α) in v.filterAt x, ρ a / μ a < ↑c) →
      (∃ᶠ (x : Set α) in v.filterAt x, ↑d < ρ x / μ x) → ∃ᶠ (a : Set α) in v.filterAt x, ρ a ≤ ↑c * μ a
Module: Mathlib.MeasureTheory.Covering.Differentiation

Goal state before:
pp: case hd
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
w : Set ℝ≥0∞
w_count : w.Countable
w_dense : Dense w
left✝ : 0 ∉ w
w_top : ∞ ∉ w
I : ∀ x ∈ w, x ≠ ∞
c : ℝ≥0
hc : ↑c ∈ w
d : ℝ≥0
hd : ↑d ∈ w
hcd : ↑c < ↑d
⊢ ∀
    x ∈
      {x |
          (fun x ↦ ¬((∃ᶠ (a : Set α) in v.filterAt x, ρ a / μ a < ↑c) ∧ ∃ᶠ (a : Set α) in v.filterAt x, ↑d < ρ a / μ a))
            x}ᶜ,
    ∃ᶠ (a : Set α) in v.filterAt x, ↑d * μ a ≤ ρ a

Tactic:
simp only [and_imp, exists_prop, not_frequently, not_and, not_lt, not_le, not_eventually,
        mem_ofPred_eq, mem_compl_iff, not_forall]

Goal state after:
case hd
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
w : Set ℝ≥0∞
w_count : w.Countable
w_dense : Dense w
left✝ : 0 ∉ w
w_top : ∞ ∉ w
I : ∀ x ∈ w, x ≠ ∞
c : ℝ≥0
hc : ↑c ∈ w
d : ℝ≥0
hd : ↑d ∈ w
hcd : ↑c < ↑d
⊢ ∀ (x : α),
    (∃ᶠ (a : Set α) in v.filterAt x, ρ a / μ a < ↑c) →
      (∃ᶠ (x : Set α) in v.filterAt x, ↑d < ρ x / μ x) → ∃ᶠ (a : Set α) in v.filterAt x, ↑d * μ a ≤ ρ a
Module: Mathlib.MeasureTheory.Measure.Decomposition.Lebesgue

Goal state before:
pp: case refine_1
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
g : ℕ → ℝ≥0∞
h✝ : Monotone g
hg₂ : Filter.Tendsto g Filter.atTop (nhds (sSup (measurableLEEval ν μ)))
f : ℕ → α → ℝ≥0∞
hf₁ : ∀ (n : ℕ), f n ∈ measurableLE ν μ
hf₂ : ∀ (n : ℕ), (fun f ↦ ∫⁻ (x : α), f x ∂ν) (f n) = g n
ξ : α → ℝ≥0∞ := ⨆ n, ⨆ k, ⨆ (_ : k ≤ n), f k
hξ : ξ = ⨆ n, ⨆ k, ⨆ (_ : k ≤ n), f k
hξ₁ : sSup (measurableLEEval ν μ) = ∫⁻ (a : α), ξ a ∂ν
hξm : Measurable ξ
hξle : ∀ (A : Set α), MeasurableSet A → ∫⁻ (a : α) in A, ξ a ∂ν ≤ μ A
hle : ν.withDensity ξ ≤ μ
this✝¹ : IsFiniteMeasure (ν.withDensity ξ)
μ₁ : Measure α := μ - ν.withDensity ξ
hμ₁ : μ₁ = μ - ν.withDensity ξ
h : ¬(μ₁, ξ).1 ⟂ₘ ν
ε : ℝ≥0
hε₁ : 0 < ε
E : Set α
hE₁ : MeasurableSet E
hE₂ : 0 < ν E
hE₃ : ∀ (A : Set α), MeasurableSet A → ↑ε * ν (A ∩ E) ≤ (μ - ν.withDensity ξ) (A ∩ E)
hε₂ : ∀ (A : Set α), MeasurableSet A → ∫⁻ (a : α) in A ∩ E, ↑ε + ξ a ∂ν ≤ μ (A ∩ E)
hξε : (ξ + E.indicator fun x ↦ ↑ε) ∈ measurableLE ν μ
this✝ : ∫⁻ (a : α), ξ a + E.indicator (fun x ↦ ↑ε) a ∂ν ≤ sSup (measurableLEEval ν μ)
this : (ν.withDensity ξ) univ ≠ ∞
⊢ ∫⁻ (a : α), ξ a ∂ν ≠ ∞

Tactic:
withDensity_apply _ MeasurableSet.univ,

Goal state after:
case refine_1
α : Type u_1
m : MeasurableSpace α
μ ν : Measure α
inst✝¹ : IsFiniteMeasure μ
inst✝ : IsFiniteMeasure ν
g : ℕ → ℝ≥0∞
h✝ : Monotone g
hg₂ : Filter.Tendsto g Filter.atTop (nhds (sSup (measurableLEEval ν μ)))
f : ℕ → α → ℝ≥0∞
hf₁ : ∀ (n : ℕ), f n ∈ measurableLE ν μ
hf₂ : ∀ (n : ℕ), (fun f ↦ ∫⁻ (x : α), f x ∂ν) (f n) = g n
ξ : α → ℝ≥0∞ := ⨆ n, ⨆ k, ⨆ (_ : k ≤ n), f k
hξ : ξ = ⨆ n, ⨆ k, ⨆ (_ : k ≤ n), f k
hξ₁ : sSup (measurableLEEval ν μ) = ∫⁻ (a : α), ξ a ∂ν
hξm : Measurable ξ
hξle : ∀ (A : Set α), MeasurableSet A → ∫⁻ (a : α) in A, ξ a ∂ν ≤ μ A
hle : ν.withDensity ξ ≤ μ
this✝¹ : IsFiniteMeasure (ν.withDensity ξ)
μ₁ : Measure α := μ - ν.withDensity ξ
hμ₁ : μ₁ = μ - ν.withDensity ξ
h : ¬(μ₁, ξ).1 ⟂ₘ ν
ε : ℝ≥0
hε₁ : 0 < ε
E : Set α
hE₁ : MeasurableSet E
hE₂ : 0 < ν E
hE₃ : ∀ (A : Set α), MeasurableSet A → ↑ε * ν (A ∩ E) ≤ (μ - ν.withDensity ξ) (A ∩ E)
hε₂ : ∀ (A : Set α), MeasurableSet A → ∫⁻ (a : α) in A ∩ E, ↑ε + ξ a ∂ν ≤ μ (A ∩ E)
hξε : (ξ + E.indicator fun x ↦ ↑ε) ∈ measurableLE ν μ
this✝ : ∫⁻ (a : α), ξ a + E.indicator (fun x ↦ ↑ε) a ∂ν ≤ sSup (measurableLEEval ν μ)
this : ∫⁻ (a : α) in univ, ξ a ∂ν ≠ ∞
⊢ ∫⁻ (a : α), ξ a ∂ν ≠ ∞
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 : α
as : a ∈ s
⊢ MonotoneOn (variationOnFromTo f s a) s

Tactic:
by
  rintro b bs c cs bc
  rw [← variationOnFromTo.add hf as bs cs]
  exact le_add_of_nonneg_right (variationOnFromTo.nonneg_of_le f s bc)

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 : SigmaFinite ν
inst✝ : SigmaFinite μ
r : ℝ≥0
⊢ (r • ν).rnDeriv μ =ᵐ[μ] r • ν.rnDeriv μ

Tactic:
rw [← withDensity_eq_iff_of_sigmaFinite]
  · simp_rw [ENNReal.smul_def]
    rw [withDensity_smul _ (measurable_rnDeriv _ _)]
    suffices (r • ν).singularPart μ + withDensity μ (rnDeriv (r • ν) μ)
        = (r • ν).singularPart μ + r • withDensity μ (rnDeriv ν μ) by
      rwa [Measure.add_right_inj] at this
    rw [← (r • ν).haveLebesgueDecomposition_add μ, singularPart_smul, ← smul_add,
      ← ν.haveLebesgueDecomposition_add μ]
  · exact (measurable_rnDeriv _ _).aemeasurable
  · exact (measurable_rnDeriv _ _).aemeasurable.const_smul _

Goal state after:
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 ∩ Ioi b] b) (𝓝 l)
⊢ Tendsto (variationOnFromTo f s a) (𝓝[s ∩ Ioi b] b) (𝓝 (variationOnFromTo f s a b + dist (f b) l))

Tactic:
suffices H : Tendsto (fun x ↦ variationOnFromTo f s a b + variationOnFromTo f s b x)
      (𝓝[s ∩ Ioi b] b) (𝓝 (variationOnFromTo f s a b + dist (f b) l)) by
    apply Tendsto.congr' _ H
    filter_upwards [self_mem_nhdsWithin] with x hx
    rw [variationOnFromTo.add hf ha hb hx.1]

Goal state after:
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 ∩ Ioi b] b) (𝓝 l)
⊢ Tendsto (fun x ↦ variationOnFromTo f s a b + variationOnFromTo f s b x) (𝓝[s ∩ Ioi b] b)
    (𝓝 (variationOnFromTo f s a b + dist (f b) l))
Module: Mathlib.Topology.EMetricSpace.BoundedVariation

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
x : α
hx : x ∈ s
u : ℕ → α
hu : Monotone u
us : ∀ (i : ℕ), u i ∈ s
n : ℕ
h : u n ≤ x
v : ℕ → α := fun i ↦ if i ≤ n then u i else x
⊢ ∑ i ∈ Finset.range n, edist (f (v (i + 1))) (f (v i)) ≤ ∑ j ∈ Finset.range (n + 2), edist (f (v (j + 1))) (f (v j))

Tactic:
gcongr
        apply Nat.le_add_right

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

Goal state before:
pp: α : Type u_1
m : MeasurableSpace α
ν₁ ν₂ μ : Measure α
inst✝² : SigmaFinite ν₁
inst✝¹ : SigmaFinite ν₂
inst✝ : SigmaFinite μ
h : ν₂ ⟂ₘ μ
x : α
⊢ (ν₁ + ν₂).rnDeriv μ x = (ν₁.rnDeriv μ + ν₂.rnDeriv μ) x →
    ν₂.rnDeriv μ x = 0 x → (ν₁ + ν₂).rnDeriv μ x = ν₁.rnDeriv μ x

Tactic:
hx_add

Goal state after:
α : Type u_1
m : MeasurableSpace α
ν₁ ν₂ μ : Measure α
inst✝² : SigmaFinite ν₁
inst✝¹ : SigmaFinite ν₂
inst✝ : SigmaFinite μ
h : ν₂ ⟂ₘ μ
x : α
hx_add : (ν₁ + ν₂).rnDeriv μ x = (ν₁.rnDeriv μ + ν₂.rnDeriv μ) x
⊢ ν₂.rnDeriv μ x = 0 x → (ν₁ + ν₂).rnDeriv μ x = ν₁.rnDeriv μ x
Module: Mathlib.Analysis.BoundedVariation

Goal state before:
pp: α : Type u_2
inst✝⁷ : LinearOrder α
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
𝕜 : Type u_6
f : α → 𝕜
g : α → F
inst✝⁴ : NormedRing 𝕜
inst✝³ : NormedAlgebra ℝ 𝕜
inst✝² : Module 𝕜 F
inst✝¹ : NormSMulClass 𝕜 F
inst✝ : IsScalarTower ℝ 𝕜 F
C D : ℝ≥0∞
s : Set α
hf : ∀ x ∈ s, ‖f x‖ₑ ≤ C
hg : ∀ x ∈ s, ‖g x‖ₑ ≤ D
⊢ 1 * (C * eVariationOn g s + D * eVariationOn f s) ≤ C * eVariationOn g s + D * eVariationOn f s

Tactic:
one_mul

Goal state after:
α : Type u_2
inst✝⁷ : LinearOrder α
F : Type u_4
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
𝕜 : Type u_6
f : α → 𝕜
g : α → F
inst✝⁴ : NormedRing 𝕜
inst✝³ : NormedAlgebra ℝ 𝕜
inst✝² : Module 𝕜 F
inst✝¹ : NormSMulClass 𝕜 F
inst✝ : IsScalarTower ℝ 𝕜 F
C D : ℝ≥0∞
s : Set α
hf : ∀ x ∈ s, ‖f x‖ₑ ≤ C
hg : ∀ x ∈ s, ‖g x‖ₑ ≤ D
⊢ C * eVariationOn g s + D * eVariationOn f s ≤ C * eVariationOn g s + D * eVariationOn f s
Module: Mathlib.Topology.ContinuousMap.StarOrdered

Goal state before:
pp: case h
α : Type u_1
inst✝⁸ : TopologicalSpace α
R : Type u_2
inst✝⁷ : PartialOrder R
inst✝⁶ : NonUnitalSemiring R
inst✝⁵ : StarRing R
inst✝⁴ : StarOrderedRing R
inst✝³ : TopologicalSpace R
inst✝² : ContinuousStar R
inst✝¹ : IsTopologicalSemiring R
inst✝ : ContinuousSqrt R
f g : C(α, R)
h : ∀ (a : α), f a ≤ g a
x : α
⊢ g x =
    (f +
        star
            ({ toFun := {x | x.1 ≤ x.2}.domRestrict ContinuousSqrt.sqrt, continuous_toFun := ⋯ }.comp
              { toFun := Set.codRestrict ⇑(f.prodMk g) {x | x.1 ≤ x.2} h, continuous_toFun := ⋯ }) *
          { toFun := {x | x.1 ≤ x.2}.domRestrict ContinuousSqrt.sqrt, continuous_toFun := ⋯ }.comp
            { toFun := Set.codRestrict ⇑(f.prodMk g) {x | x.1 ≤ x.2} h, continuous_toFun := ⋯ })
      x

Tactic:
simpa [IsSelfAdjoint.star_eq <| .of_nonneg (ContinuousSqrt.sqrt_nonneg (f x, g x) (h x))]
      using ContinuousSqrt.sqrt_mul_sqrt (f x, g x) (h x)

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

Goal state before:
pp: α : Type u_1
inst✝¹ : LinearOrder α
E : Type u_2
inst✝ : PseudoEMetricSpace E
f : α → E
s t : Set α
h : ∀ x ∈ s, ∀ y ∈ t, x ≤ y
hs : ¬s = ∅
this✝ : Nonempty { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ s }
ht : ¬t = ∅
this : Nonempty { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ t }
n : ℕ
u : ℕ → α
hu : Monotone u
us : ∀ (i : ℕ), u i ∈ s
m : ℕ
v : ℕ → α
hv : Monotone v
vt : ∀ (i : ℕ), v i ∈ t
w : ℕ → α := fun i ↦ if i ≤ n then u i else v (i - (n + 1))
⊢ Disjoint (Finset.range n) (Finset.Ico (n + 1) (n + 1 + m))

Tactic:
exact Finset.disjoint_left.2 (by grind)

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

Goal state before:
pp: case h₁
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} := ⋯
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 < ∞
⊢ ∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ ≤ ε / 2 * μ a

Tactic:
rw [ENNReal.div_lt_iff (Or.inl h'a.ne') (Or.inl h''a.ne)] at ha

Goal state after:
case h₁
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 < ε / 2 * μ a
h'a : 0 < μ a
h''a : μ a < ∞
⊢ ∫⁻ (y : α) in a, ‖f y - c‖ₑ ∂μ ≤ ε / 2 * μ a
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unital

Goal state before:
pp: case pos
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁸ : CommSemiring R
inst✝⁷ : StarRing R
inst✝⁶ : MetricSpace R
inst✝⁵ : IsTopologicalSemiring R
inst✝⁴ : ContinuousStar R
inst✝³ : TopologicalSpace A
inst✝² : Ring A
inst✝¹ : StarRing A
inst✝ : Algebra R A
instCFC : ContinuousFunctionalCalculus R A p
ι : Type u_3
f : ι → R → R
a : A
s : Finset ι
hf : ∀ i ∈ s, ContinuousOn (f i) (spectrum R a)
ha : p a
hsum : s.sum f = fun z ↦ ∑ i ∈ s, f i z
⊢ cfc (∑ i ∈ s, f i) a = ∑ i ∈ s, cfc (f i) a

Tactic:
have hf' : ContinuousOn (∑ i : s, f i) (spectrum R a) := by
      rw [sum_coe_sort s, hsum]
      exact continuousOn_finsetSum s fun i hi => hf i hi

Goal state after:
case pos
R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁸ : CommSemiring R
inst✝⁷ : StarRing R
inst✝⁶ : MetricSpace R
inst✝⁵ : IsTopologicalSemiring R
inst✝⁴ : ContinuousStar R
inst✝³ : TopologicalSpace A
inst✝² : Ring A
inst✝¹ : StarRing A
inst✝ : Algebra R A
instCFC : ContinuousFunctionalCalculus R A p
ι : Type u_3
f : ι → R → R
a : A
s : Finset ι
hf : ∀ i ∈ s, ContinuousOn (f i) (spectrum R a)
ha : p a
hsum : s.sum f = fun z ↦ ∑ i ∈ s, f i z
hf' : ContinuousOn (∑ i, f ↑i) (spectrum R a)
⊢ cfc (∑ i ∈ s, f i) a = ∑ i ∈ s, cfc (f i) a
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unital

Goal state before:
pp: R : Type u_1
A : Type u_2
p : A → Prop
inst✝⁸ : CommSemiring R
inst✝⁷ : StarRing R
inst✝⁶ : MetricSpace R
inst✝⁵ : IsTopologicalSemiring R
inst✝⁴ : ContinuousStar R
inst✝³ : TopologicalSpace A
inst✝² : Ring A
inst✝¹ : StarRing A
inst✝ : Algebra R A
instCFC : ContinuousFunctionalCalculus R A p
q : R[X]
f : R → R
a : A
ha : p a
hf : ContinuousOn f (spectrum R a)
⊢ cfc (fun x ↦ Polynomial.eval (f x) q) a = (aeval (cfc f a)) q

Tactic:
induction q using Polynomial.induction_on with

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

Goal state before:
pp: R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : IsTopologicalSemiring R
X : Set R
x✝ : C(↑X, R)
⊢ x✝ ∈ ↑(polynomialFunctions X) ↔ x✝ ∈ Set.range ⇑(toContinuousMapOnAlgHom X)

Tactic:
simp [polynomialFunctions]

Goal state after:
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
this :
  Continuous fun x ↦
    match x with
    | (x, y) => gauge U (f x - f y)
⊢ ∃ C, ∀ (x y : ↑I), gauge U (f x - f y) ≤ C

Tactic:
simpa only [BddAbove, Set.Nonempty, mem_upperBounds, Set.forall_mem_range, Prod.forall]
      using isCompact_range this |>.bddAbove

Goal state after:
Module: Mathlib.RingTheory.Polynomial.Bernstein

Goal state before:
pp: case calc_1
R : Type u_1
inst✝ : CommRing R
n : ℕ
p :
  ∑ x ∈ Finset.range (n + 1),
      (↑(x * (x - 1)) + (1 - ↑(2 * n) * X) * ↑x + ↑(n ^ 2) * X ^ 2) * bernsteinPolynomial R n x =
    ↑(n * (n - 1)) * X ^ 2 + (1 - (2 * n) • X) * n • X + n ^ 2 • X ^ 2 * 1
k : ℕ
m : k ∈ Finset.range (n + 1)
⊢ (n • X - ↑k) ^ 2 * bernsteinPolynomial R n k =
    (↑(k * (k - 1)) + (1 - ↑(2 * n) * X) * ↑k + ↑(n ^ 2) * X ^ 2) * bernsteinPolynomial R n k

pp: case calc_2
R : Type u_1
inst✝ : CommRing R
n : ℕ
p :
  ∑ x ∈ Finset.range (n + 1),
      (↑(x * (x - 1)) + (1 - ↑(2 * n) * X) * ↑x + ↑(n ^ 2) * X ^ 2) * bernsteinPolynomial R n x =
    ↑(n * (n - 1)) * X ^ 2 + (1 - (2 * n) • X) * n • X + n ^ 2 • X ^ 2 * 1
⊢ ↑(n * (n - 1)) * X ^ 2 + (1 - (2 * n) • X) * n • X + n ^ 2 • X ^ 2 * 1 = n • X * (1 - X)

Tactic:
· congr 1; simp only [← natCast_mul, push_cast]
    cases k <;> · simp; ring

Goal state after:
case calc_2
R : Type u_1
inst✝ : CommRing R
n : ℕ
p :
  ∑ x ∈ Finset.range (n + 1),
      (↑(x * (x - 1)) + (1 - ↑(2 * n) * X) * ↑x + ↑(n ^ 2) * X ^ 2) * bernsteinPolynomial R n x =
    ↑(n * (n - 1)) * X ^ 2 + (1 - (2 * n) • X) * n • X + n ^ 2 • X ^ 2 * 1
⊢ ↑(n * (n - 1)) * X ^ 2 + (1 - (2 * n) • X) * n • X + n ^ 2 • X ^ 2 * 1 = n • X * (1 - X)
Module: Mathlib.Analysis.CStarAlgebra.ContinuousFunctionalCalculus.Unique

Goal state before:
pp: X : Type u_1
inst✝⁵ : TopologicalSpace X
A : Type u_2
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : Algebra ℝ A
inst✝¹ : TopologicalSpace A
inst✝ : IsSemitopologicalRing A
φ : C(X, ℝ≥0) →⋆ₐ[ℝ≥0] A
f g : C(X, ℝ)
this :
  φ ((f * g).toNNReal + (-f).toNNReal * g.toNNReal + f.toNNReal * (-g).toNNReal) =
    φ ((-(f * g)).toNNReal + f.toNNReal * g.toNNReal + (-f).toNNReal * (-g).toNNReal)
⊢ φ (f * g).toNNReal - φ (-(f * g)).toNNReal = (φ f.toNNReal - φ (-f).toNNReal) * (φ g.toNNReal - φ (-g).toNNReal)

Tactic:
simp only [map_add, map_mul, sub_mul, mul_sub] at this ⊢

Goal state after:
X : Type u_1
inst✝⁵ : TopologicalSpace X
A : Type u_2
inst✝⁴ : Ring A
inst✝³ : StarRing A
inst✝² : Algebra ℝ A
inst✝¹ : TopologicalSpace A
inst✝ : IsSemitopologicalRing A
φ : C(X, ℝ≥0) →⋆ₐ[ℝ≥0] A
f g : C(X, ℝ)
this :
  φ (f * g).toNNReal + φ (-f).toNNReal * φ g.toNNReal + φ f.toNNReal * φ (-g).toNNReal =
    φ (-(f * g)).toNNReal + φ f.toNNReal * φ g.toNNReal + φ (-f).toNNReal * φ (-g).toNNReal
⊢ φ (f * g).toNNReal - φ (-(f * g)).toNNReal =
    φ f.toNNReal * φ g.toNNReal - φ (-f).toNNReal * φ g.toNNReal -
      (φ f.toNNReal * φ (-g).toNNReal - φ (-f).toNNReal * φ (-g).toNNReal)