mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Analysis.Calculus.ContDiff.Bounds

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type uE
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type uF
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type uG
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
g : F → G
f : E → F
n : ℕ
s : Set E
t : Set F
x : E
N : ℕ∞ω
hg : ContDiffOn 𝕜 N g t
hf : ContDiffOn 𝕜 N f s
hn : ↑n ≤ N
ht : UniqueDiffOn 𝕜 t
hs : UniqueDiffOn 𝕜 s
hst : MapsTo f s t
hx : x ∈ s
C D : ℝ
Fu : Type (max uF uG) := ULift.{uG, uF} F
Gu : Type (max uF uG) := ULift.{uF, uG} G
isoF : Fu ≃ₗᵢ[𝕜] F
isoG : Gu ≃ₗᵢ[𝕜] G
fu : E → Fu := ⇑isoF.symm ∘ f
gu : Fu → Gu := ⇑isoG.symm ∘ g ∘ ⇑isoF
tu : Set Fu := ⇑isoF ⁻¹' t
htu : UniqueDiffOn 𝕜 tu
hstu : MapsTo fu s tu
Ffu : isoF (fu x) = f x
hfu : ContDiffOn 𝕜 (↑n) fu s
hgu : ContDiffOn 𝕜 (↑n) gu tu
Nfu : ∀ (i : ℕ), ‖iteratedFDerivWithin 𝕜 i fu s x‖ = ‖iteratedFDerivWithin 𝕜 i f s x‖
hD : ∀ (i : ℕ), 1 ≤ i → i ≤ n → ‖iteratedFDerivWithin 𝕜 i fu s x‖ ≤ D ^ i
Ngu : ∀ (i : ℕ), ‖iteratedFDerivWithin 𝕜 i gu tu (fu x)‖ = ‖iteratedFDerivWithin 𝕜 i g t (f x)‖
hC : ∀ i ≤ n, ‖iteratedFDerivWithin 𝕜 i gu tu (fu x)‖ ≤ C
this : gu ∘ fu = ⇑isoG.symm ∘ g ∘ f
⊢ ‖iteratedFDerivWithin 𝕜 n (g ∘ f) s x‖ = ‖iteratedFDerivWithin 𝕜 n (gu ∘ fu) s x‖

Tactic:
this,

Goal state after:
𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type uE
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
F : Type uF
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
G : Type uG
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
g : F → G
f : E → F
n : ℕ
s : Set E
t : Set F
x : E
N : ℕ∞ω
hg : ContDiffOn 𝕜 N g t
hf : ContDiffOn 𝕜 N f s
hn : ↑n ≤ N
ht : UniqueDiffOn 𝕜 t
hs : UniqueDiffOn 𝕜 s
hst : MapsTo f s t
hx : x ∈ s
C D : ℝ
Fu : Type (max uF uG) := ULift.{uG, uF} F
Gu : Type (max uF uG) := ULift.{uF, uG} G
isoF : Fu ≃ₗᵢ[𝕜] F
isoG : Gu ≃ₗᵢ[𝕜] G
fu : E → Fu := ⇑isoF.symm ∘ f
gu : Fu → Gu := ⇑isoG.symm ∘ g ∘ ⇑isoF
tu : Set Fu := ⇑isoF ⁻¹' t
htu : UniqueDiffOn 𝕜 tu
hstu : MapsTo fu s tu
Ffu : isoF (fu x) = f x
hfu : ContDiffOn 𝕜 (↑n) fu s
hgu : ContDiffOn 𝕜 (↑n) gu tu
Nfu : ∀ (i : ℕ), ‖iteratedFDerivWithin 𝕜 i fu s x‖ = ‖iteratedFDerivWithin 𝕜 i f s x‖
hD : ∀ (i : ℕ), 1 ≤ i → i ≤ n → ‖iteratedFDerivWithin 𝕜 i fu s x‖ ≤ D ^ i
Ngu : ∀ (i : ℕ), ‖iteratedFDerivWithin 𝕜 i gu tu (fu x)‖ = ‖iteratedFDerivWithin 𝕜 i g t (f x)‖
hC : ∀ i ≤ n, ‖iteratedFDerivWithin 𝕜 i gu tu (fu x)‖ ≤ C
this : gu ∘ fu = ⇑isoG.symm ∘ g ∘ f
⊢ ‖iteratedFDerivWithin 𝕜 n (g ∘ f) s x‖ = ‖iteratedFDerivWithin 𝕜 n (⇑isoG.symm ∘ g ∘ f) s x‖
Module: Mathlib.MeasureTheory.Covering.Besicovitch

Goal state before:
pp: case neg
α : Type u_1
inst✝⁶ : MetricSpace α
inst✝⁵ : SecondCountableTopology α
inst✝⁴ : MeasurableSpace α
inst✝³ : OpensMeasurableSpace α
inst✝² : HasBesicovitchCovering α
μ : Measure α
inst✝¹ : SFinite μ
inst✝ : μ.OuterRegular
ε : ℝ≥0∞
hε : ε ≠ 0
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
u : Set α
su : u ⊇ s
u_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] u
μu : μ u ≤ μ s + ε / 2
R : α → ℝ
hR : ∀ x ∈ s, R x > 0 ∧ ball x (R x) ⊆ u
t0 : Set α
r0 : α → ℝ
t0_count : t0.Countable
t0s : t0 ⊆ s
hr0 : ∀ x ∈ t0, r0 x ∈ f x ∩ Ioo 0 (R x)
μt0 : μ (s \ ⋃ x ∈ t0, closedBall x (r0 x)) = 0
t0_disj : t0.PairwiseDisjoint fun x ↦ closedBall x (r0 x)
s' : Set α := s \ ⋃ x ∈ t0, closedBall x (r0 x)
s's : s' ⊆ s
N : ℕ
τ : ℝ
hτ : 1 < τ
H : IsEmpty (SatelliteConfig α N τ)
v : Set α
s'v : v ⊇ s'
v_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] v
μv : μ v ≤ μ s' + ε / 2 / ↑N
r1 : α → ℝ
hr1 : ∀ x ∈ s', r1 x ∈ f x ∩ Ioo 0 1 ∧ closedBall x (r1 x) ⊆ v
q : BallPackage (↑s') α := { c := fun x ↦ ↑x, r := fun x ↦ r1 ↑x, rpos := ⋯, r_bound := 1, r_le := ⋯ }
S : Fin N → Set ↑s'
S_disj : ∀ (i : Fin N), (S i).PairwiseDisjoint fun j ↦ closedBall (q.c j) (q.r j)
hS : range q.c ⊆ ⋃ i, ⋃ j ∈ S i, ball (q.c j) (q.r j)
S_count : ∀ (i : Fin N), (S i).Countable
r : α → ℝ := fun x ↦ if x ∈ s' then r1 x else r0 x
r_t0 : ∀ x ∈ t0, r x = r0 x
x : α
hx : x ∈ s
h'x : x ∉ s'
y : α
yt0 : y ∈ t0
hxy : x ∈ closedBall y (r0 y)
⊢ x ∈ closedBall y (r y)

Tactic:
rwa [r_t0 _ yt0]

Goal state after:
Module: Mathlib.Analysis.Calculus.FDeriv.Symmetric

Goal state before:
pp: E : Type u_1
F : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℝ E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
s : Set E
s_conv : Convex ℝ s
f : E → F
f' : E → E →L[ℝ] F
f'' : E →L[ℝ] E →L[ℝ] F
hf : ∀ x ∈ interior s, HasFDerivAt f (f' x) x
x : E
xs : x ∈ s
hx : ∀ ⦃c : ℝ⦄, 0 < c → ∀ᶠ (x_1 : E) in 𝓝[interior s] x, ‖f' x_1 - f' x - f'' (x_1 - x)‖ ≤ c * ‖x_1 - x‖
v w : E
hv : x + v ∈ interior s
hw : x + v + w ∈ interior s
ε : ℝ
εpos : 0 < ε
δ : ℝ
δpos : δ > 0
sδ : Metric.ball x δ ∩ interior s ⊆ {x_1 | (fun x_2 ↦ ‖f' x_2 - f' x - f'' (x_2 - x)‖ ≤ ε * ‖x_2 - x‖) x_1}
E1 : ∀ᶠ (h : ℝ) in 𝓝[>] 0, h * (‖v‖ + ‖w‖) < δ
E2 : ∀ᶠ (h : ℝ) in 𝓝[>] 0, h < 1
h : ℝ
hδ : h * (‖v‖ + ‖w‖) < δ
h_lt_1 : h < 1
hpos : 0 < h
xt_mem : ∀ t ∈ Icc 0 1, x + h • v + (t * h) • w ∈ interior s
g : ℝ → F :=
  fun t ↦ f (x + h • v + (t * h) • w) - (t * h) • (f' x) w - (t * h ^ 2) • (f'' v) w - ((t * h) ^ 2 / 2) • (f'' w) w
g' : ℝ → F :=
  fun t ↦ (f' (x + h • v + (t * h) • w)) (h • w) - h • (f' x) w - h ^ 2 • (f'' v) w - (t * h ^ 2) • (f'' w) w
hg' : g' = fun t ↦ (f' (x + h • v + (t * h) • w)) (h • w) - h • (f' x) w - h ^ 2 • (f'' v) w - (t * h ^ 2) • (f'' w) w
g_deriv : ∀ t ∈ Icc 0 1, HasDerivWithinAt g (g' t) (Icc 0 1) t
t : ℝ
ht : t ∈ Ico 0 1
I : ‖h • v + (t * h) • w‖ ≤ h * (‖v‖ + ‖w‖)
⊢ ε * ‖h • v + (t * h) • w‖ * ‖h • w‖ ≤ ε * (‖h • v‖ + ‖h • w‖) * ‖h • w‖

Tactic:
gcongr
        apply (norm_add_le _ _).trans
        gcongr
        simp only [norm_smul, Real.norm_eq_abs, abs_mul, abs_of_nonneg, ht.1, hpos.le, mul_assoc]
        exact mul_le_of_le_one_left (by positivity) ht.2.le

Goal state after:
Module: Mathlib.Analysis.Calculus.FDeriv.ContinuousAlternatingMap

Goal state before:
pp: case intro
𝕜 : Type u_1
ι : Type u_2
E : Type u_3
F : Type u_4
G : Type u_5
inst✝⁷ : NontriviallyNormedField 𝕜
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace 𝕜 E
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace 𝕜 F
inst✝² : NormedAddCommGroup G
inst✝¹ : NormedSpace 𝕜 G
f : E → F [⋀^ι]→L[𝕜] G
g : ι → E → F
x : E
inst✝ : Finite ι
hf : DifferentiableAt 𝕜 f x
hg : ∀ (i : ι), DifferentiableAt 𝕜 (g i) x
val✝ : Fintype ι
⊢ DifferentiableAt 𝕜 (fun x ↦ (f x) fun x_1 ↦ g x_1 x) x

Tactic:
classical
  exact hf.hasFDerivAt.continuousAlternatingMap_apply (fun i ↦ (hg i).hasFDerivAt)
    |>.differentiableAt

Goal state after:
Module: Mathlib.Analysis.Calculus.LineDeriv.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
F : Type u_2
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
f : E → F
f' : F
s t : Set E
x v : E
h : HasLineDerivWithinAt 𝕜 f f' t x v
hst : t ∈ 𝓝[s] x
⊢ (fun t ↦ x + t • v) ⁻¹' t ∈ 𝓝[(fun t ↦ x + t • v) ⁻¹' s] 0

Tactic:
apply ContinuousWithinAt.preimage_mem_nhdsWithin'' _ hst (by simp)

Goal state after:
𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
F : Type u_2
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
f : E → F
f' : F
s t : Set E
x v : E
h : HasLineDerivWithinAt 𝕜 f f' t x v
hst : t ∈ 𝓝[s] x
⊢ ContinuousWithinAt (fun t ↦ x + t • v) ((fun t ↦ x + t • v) ⁻¹' s) 0
Module: Mathlib.MeasureTheory.Covering.Besicovitch

Goal state before:
pp: α : Type u_1
inst✝⁶ : MetricSpace α
inst✝⁵ : SecondCountableTopology α
inst✝⁴ : MeasurableSpace α
inst✝³ : OpensMeasurableSpace α
inst✝² : HasBesicovitchCovering α
μ : Measure α
inst✝¹ : SFinite μ
inst✝ : μ.OuterRegular
ε : ℝ≥0∞
hε : ε ≠ 0
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
u : Set α
su : u ⊇ s
u_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] u
μu : μ u ≤ μ s + ε / 2
R : α → ℝ
hR : ∀ x ∈ s, R x > 0 ∧ ball x (R x) ⊆ u
t0 : Set α
r0 : α → ℝ
t0_count : t0.Countable
t0s : t0 ⊆ s
hr0 : ∀ x ∈ t0, r0 x ∈ f x ∩ Ioo 0 (R x)
μt0 : μ (s \ ⋃ x ∈ t0, closedBall x (r0 x)) = 0
t0_disj : t0.PairwiseDisjoint fun x ↦ closedBall x (r0 x)
s' : Set α := s \ ⋃ x ∈ t0, closedBall x (r0 x)
s's : s' ⊆ s
N : ℕ
τ : ℝ
hτ : 1 < τ
H : IsEmpty (SatelliteConfig α N τ)
v : Set α
s'v : v ⊇ s'
v_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] v
μv : μ v ≤ μ s' + ε / 2 / ↑N
r1 : α → ℝ
hr1 : ∀ x ∈ s', r1 x ∈ f x ∩ Ioo 0 1 ∧ closedBall x (r1 x) ⊆ v
q : BallPackage (↑s') α := { c := fun x ↦ ↑x, r := fun x ↦ r1 ↑x, rpos := ⋯, r_bound := 1, r_le := ⋯ }
S : Fin N → Set ↑s'
S_disj : ∀ (i : Fin N), (S i).PairwiseDisjoint fun j ↦ closedBall (q.c j) (q.r j)
hS : range q.c ⊆ ⋃ i, ⋃ j ∈ S i, ball (q.c j) (q.r j)
S_count : ∀ (i : Fin N), (S i).Countable
r : α → ℝ := fun x ↦ if x ∈ s' then r1 x else r0 x
r_t0 : ∀ x ∈ t0, r x = r0 x
A : ∑' (x : ↑t0), μ (closedBall (↑x) (r ↑x)) ≤ μ s + ε / 2
i : Fin N
this : μ s' = 0
⊢ μ v ≤ ε / 2 / ↑N

Tactic:
this,

Goal state after:
α : Type u_1
inst✝⁶ : MetricSpace α
inst✝⁵ : SecondCountableTopology α
inst✝⁴ : MeasurableSpace α
inst✝³ : OpensMeasurableSpace α
inst✝² : HasBesicovitchCovering α
μ : Measure α
inst✝¹ : SFinite μ
inst✝ : μ.OuterRegular
ε : ℝ≥0∞
hε : ε ≠ 0
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
u : Set α
su : u ⊇ s
u_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] u
μu : μ u ≤ μ s + ε / 2
R : α → ℝ
hR : ∀ x ∈ s, R x > 0 ∧ ball x (R x) ⊆ u
t0 : Set α
r0 : α → ℝ
t0_count : t0.Countable
t0s : t0 ⊆ s
hr0 : ∀ x ∈ t0, r0 x ∈ f x ∩ Ioo 0 (R x)
μt0 : μ (s \ ⋃ x ∈ t0, closedBall x (r0 x)) = 0
t0_disj : t0.PairwiseDisjoint fun x ↦ closedBall x (r0 x)
s' : Set α := s \ ⋃ x ∈ t0, closedBall x (r0 x)
s's : s' ⊆ s
N : ℕ
τ : ℝ
hτ : 1 < τ
H : IsEmpty (SatelliteConfig α N τ)
v : Set α
s'v : v ⊇ s'
v_open : IsOpen[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] v
μv : μ v ≤ 0 + ε / 2 / ↑N
r1 : α → ℝ
hr1 : ∀ x ∈ s', r1 x ∈ f x ∩ Ioo 0 1 ∧ closedBall x (r1 x) ⊆ v
q : BallPackage (↑s') α := { c := fun x ↦ ↑x, r := fun x ↦ r1 ↑x, rpos := ⋯, r_bound := 1, r_le := ⋯ }
S : Fin N → Set ↑s'
S_disj : ∀ (i : Fin N), (S i).PairwiseDisjoint fun j ↦ closedBall (q.c j) (q.r j)
hS : range q.c ⊆ ⋃ i, ⋃ j ∈ S i, ball (q.c j) (q.r j)
S_count : ∀ (i : Fin N), (S i).Countable
r : α → ℝ := fun x ↦ if x ∈ s' then r1 x else r0 x
r_t0 : ∀ x ∈ t0, r x = r0 x
A : ∑' (x : ↑t0), μ (closedBall (↑x) (r ↑x)) ≤ μ s + ε / 2
i : Fin N
this : μ s' = 0
⊢ μ v ≤ ε / 2 / ↑N
Module: Mathlib.Analysis.Calculus.LineDeriv.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
F : Type u_2
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
v : E
f : E → F
f' : F
x₀ : E
hf : HasLineDerivAt 𝕜 f f' x₀ v
s : Set E
hs : s ∈ 𝓝 x₀
C : ℝ≥0
hlip : LipschitzOnWith C f s
⊢ ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ ↑C * ‖x - x₀‖

Tactic:
filter_upwards [hs] with x hx using hlip.norm_sub_le hx (mem_of_mem_nhds hs)

Goal state after:
Module: Mathlib.Analysis.Calculus.LineDeriv.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
F : Type u_2
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
v : E
f : E → F
x₀ : E
s : Set E
hs : s ∈ 𝓝 x₀
C : ℝ≥0
hlip : LipschitzOnWith C f s
⊢ ∀ᶠ (x : E) in 𝓝 x₀, ‖f x - f x₀‖ ≤ ↑C * ‖x - x₀‖

Tactic:
filter_upwards [hs] with x hx using hlip.norm_sub_le hx (mem_of_mem_nhds hs)

Goal state after:
Module: Mathlib.Analysis.Calculus.LineDeriv.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
F : Type u_2
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
E : Type u_3
inst✝¹ : AddCommGroup E
inst✝ : Module 𝕜 E
f : E → F
s : Set E
x v : E
f' : F
h : HasDerivWithinAt (fun t ↦ f (x + t • v)) f' ((fun t ↦ x + t • v) ⁻¹' s) 0
c : 𝕜
g : 𝕜 → 𝕜 := fun t ↦ c • t
s' : Set 𝕜 := (fun t ↦ x + t • v) ⁻¹' s
⊢ HasDerivAt g c 0

Tactic:
simpa using! (hasDerivAt_id (0 : 𝕜)).const_smul c

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

Goal state before:
pp: case inr
α : Type u_1
inst✝⁵ : MetricSpace α
β : Type u
inst✝⁴ : SecondCountableTopology α
inst✝³ : MeasurableSpace α
inst✝² : OpensMeasurableSpace α
inst✝¹ : HasBesicovitchCovering α
μ : Measure α
inst✝ : SFinite μ
s : Set α
f : α → Set (Set α)
fsubset : ∀ x ∈ s, f x ⊆ (fun r ↦ closedBall x r) '' Ioi 0
ffine : ∀ x ∈ s, ∀ ε > 0, ∃ t ∈ f x, t ⊆ closedBall x ε
g : α → Set ℝ := fun x ↦ {r | 0 < r ∧ closedBall x r ∈ f x}
x : α
xs : x ∈ s
δ : ℝ
δpos : δ > 0
r : ℝ
rpos : 0 < r
tf : closedBall x (δ / 2) ∈ f x
ht : closedBall x r ⊆ closedBall x (δ / 2)
H : δ / 2 ≤ r
this : closedBall x r = closedBall x (δ / 2)
⊢ (g x ∩ Ioo 0 δ).Nonempty

Tactic:
exact ⟨δ / 2, ⟨half_pos δpos, tf⟩, ⟨half_pos δpos, half_lt_self δpos⟩⟩

Goal state after:
Module: Mathlib.Analysis.Calculus.Gradient.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝ : RCLike 𝕜
g : 𝕜 → 𝕜
g' u : 𝕜
L' : Filter 𝕜
h : HasDerivAtFilter g g' (L' ×ˢ pure u)
⊢ HasGradientAtFilter g ((starRingEnd 𝕜) g') u L'

Tactic:
have : ContinuousLinearMap.smulRight (1 : 𝕜 →L[𝕜] 𝕜) g' = (toDual 𝕜 𝕜) (conj g') := by
    ext; simp

Goal state after:
𝕜 : Type u_1
inst✝ : RCLike 𝕜
g : 𝕜 → 𝕜
g' u : 𝕜
L' : Filter 𝕜
h : HasDerivAtFilter g g' (L' ×ˢ pure u)
this : ContinuousLinearMap.smulRight 1 g' = (toDual 𝕜 𝕜) ((starRingEnd 𝕜) g')
⊢ HasGradientAtFilter g ((starRingEnd 𝕜) g') u L'
Module: Mathlib.MeasureTheory.Function.JacobianOneDim

Goal state before:
pp: s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
u : ℝ → ℝ≥0∞
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
this : ∫⁻ (x : ℝ) in a, ENNReal.ofReal (f' x) * u (f x) = 0
⊢ ∫⁻ (a : ℝ) in a, ENNReal.ofReal (f' a) * u (f a) ∂volume +
      ∫⁻ (a : ℝ) in b ∪ c, ENNReal.ofReal (f' a) * u (f a) ∂volume =
    ∫⁻ (x : ℝ) in c, ENNReal.ofReal (f' x) * u (f x)

Tactic:
this,

Goal state after:
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
u : ℝ → ℝ≥0∞
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
this : ∫⁻ (x : ℝ) in a, ENNReal.ofReal (f' x) * u (f x) = 0
⊢ 0 + ∫⁻ (a : ℝ) in b ∪ c, ENNReal.ofReal (f' a) * u (f a) ∂volume = ∫⁻ (x : ℝ) in c, ENNReal.ofReal (f' x) * u (f x)
Module: Mathlib.MeasureTheory.Function.JacobianOneDim

Goal state before:
pp: s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
u : ℝ → ℝ≥0∞
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
this✝ : ∫⁻ (x : ℝ) in a, ENNReal.ofReal (f' x) * u (f x) = 0
this : ∫⁻ (x : ℝ) in b, ENNReal.ofReal (f' x) * u (f x) = 0
⊢ ∫⁻ (a : ℝ) in b, ENNReal.ofReal (f' a) * u (f a) ∂volume + ∫⁻ (a : ℝ) in c, ENNReal.ofReal (f' a) * u (f a) ∂volume =
    ∫⁻ (x : ℝ) in c, ENNReal.ofReal (f' x) * u (f x)

Tactic:
this,

Goal state after:
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
u : ℝ → ℝ≥0∞
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
this✝ : ∫⁻ (x : ℝ) in a, ENNReal.ofReal (f' x) * u (f x) = 0
this : ∫⁻ (x : ℝ) in b, ENNReal.ofReal (f' x) * u (f x) = 0
⊢ 0 + ∫⁻ (a : ℝ) in c, ENNReal.ofReal (f' a) * u (f a) ∂volume = ∫⁻ (x : ℝ) in c, ENNReal.ofReal (f' x) * u (f x)
Module: Mathlib.MeasureTheory.Function.JacobianOneDim

Goal state before:
pp: F : Type u_1
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
g : ℝ → F
H : IntegrableOn g (f '' s) volume
H' : IntegrableOn (fun x ↦ f' x • g (f x)) s volume
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
a_s : a ⊆ s
bc_s : b ∪ c ⊆ s
b_s : b ⊆ s
c_s : c ⊆ s
this : ∫ (x : ℝ) in a, f' x • g (f x) = 0
⊢ ∫ (x : ℝ) in a, f' x • g (f x) ∂volume + ∫ (x : ℝ) in b ∪ c, f' x • g (f x) ∂volume = ∫ (x : ℝ) in c, f' x • g (f x)

Tactic:
this,

Goal state after:
F : Type u_1
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
g : ℝ → F
H : IntegrableOn g (f '' s) volume
H' : IntegrableOn (fun x ↦ f' x • g (f x)) s volume
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
a_s : a ⊆ s
bc_s : b ∪ c ⊆ s
b_s : b ⊆ s
c_s : c ⊆ s
this : ∫ (x : ℝ) in a, f' x • g (f x) = 0
⊢ 0 + ∫ (x : ℝ) in b ∪ c, f' x • g (f x) ∂volume = ∫ (x : ℝ) in c, f' x • g (f x)
Module: Mathlib.MeasureTheory.Function.JacobianOneDim

Goal state before:
pp: F : Type u_1
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
g : ℝ → F
H : IntegrableOn g (f '' s) volume
H' : IntegrableOn (fun x ↦ f' x • g (f x)) s volume
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
a_s : a ⊆ s
bc_s : b ∪ c ⊆ s
b_s : b ⊆ s
c_s : c ⊆ s
this✝ : ∫ (x : ℝ) in a, f' x • g (f x) = 0
this : ∫ (x : ℝ) in b, f' x • g (f x) = 0
⊢ ∫ (x : ℝ) in b, f' x • g (f x) ∂volume + ∫ (x : ℝ) in c, f' x • g (f x) ∂volume = ∫ (x : ℝ) in c, f' x • g (f x)

Tactic:
this,

Goal state after:
F : Type u_1
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
s : Set ℝ
f f' : ℝ → ℝ
hs : MeasurableSet s
hf' : ∀ x ∈ s, HasDerivWithinAt f (f' x) s x
hf : MonotoneOn f s
g : ℝ → F
H : IntegrableOn g (f '' s) volume
H' : IntegrableOn (fun x ↦ f' x • g (f x)) s volume
a b c : Set ℝ
h_union : a ∪ (b ∪ c) = s
ha : MeasurableSet a
hb : MeasurableSet b
hc : MeasurableSet c
h_disj : Disjoint a (b ∪ c)
h_disj' : Disjoint b c
a_count : a.Countable
fb_count : (f '' b).Countable
deriv_b : ∀ x ∈ b, f' x = 0
deriv_c : ∀ x ∈ c, 0 ≤ f' x
inj_c : InjOn f c
a_s : a ⊆ s
bc_s : b ∪ c ⊆ s
b_s : b ⊆ s
c_s : c ⊆ s
this✝ : ∫ (x : ℝ) in a, f' x • g (f x) = 0
this : ∫ (x : ℝ) in b, f' x • g (f x) = 0
⊢ 0 + ∫ (x : ℝ) in c, f' x • g (f x) ∂volume = ∫ (x : ℝ) in c, f' x • g (f x)
Module: Mathlib.MeasureTheory.Integral.IntegralEqImproper

Goal state before:
pp: E : Type u_1
f f' : ℝ → E
a : ℝ
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
hderiv : ∀ x ∈ Ioi a, HasDerivAt f (f' x) x
f'int : IntegrableOn f' (Ioi a) volume
ε : ℝ
εpos : ε > 0
A : ∀ᶠ (n : ℕ) in atTop, ∫ (x : ℝ) in Ici ↑n, ‖f' x‖ < ε
B : ∀ᶠ (n : ℕ) in atTop, a < ↑n
N : ℕ
hN : ∫ (x : ℝ) in Ici ↑N, ‖f' x‖ < ε
h'N : a < ↑N
x : ℝ
hx : x ≥ ↑N
⊢ ‖f x - f ↑N‖ = ‖∫ (t : ℝ) in Ioc (↑N) x, f' t‖

Tactic:
rw [← intervalIntegral.integral_of_le hx, intervalIntegral.integral_eq_sub_of_hasDerivAt]

Goal state after:
case hderiv
E : Type u_1
f f' : ℝ → E
a : ℝ
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
hderiv : ∀ x ∈ Ioi a, HasDerivAt f (f' x) x
f'int : IntegrableOn f' (Ioi a) volume
ε : ℝ
εpos : ε > 0
A : ∀ᶠ (n : ℕ) in atTop, ∫ (x : ℝ) in Ici ↑n, ‖f' x‖ < ε
B : ∀ᶠ (n : ℕ) in atTop, a < ↑n
N : ℕ
hN : ∫ (x : ℝ) in Ici ↑N, ‖f' x‖ < ε
h'N : a < ↑N
x : ℝ
hx : x ≥ ↑N
⊢ ∀ x_1 ∈ [[↑N, x]], HasDerivAt f (f' x_1) x_1

case hint
E : Type u_1
f f' : ℝ → E
a : ℝ
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
hderiv : ∀ x ∈ Ioi a, HasDerivAt f (f' x) x
f'int : IntegrableOn f' (Ioi a) volume
ε : ℝ
εpos : ε > 0
A : ∀ᶠ (n : ℕ) in atTop, ∫ (x : ℝ) in Ici ↑n, ‖f' x‖ < ε
B : ∀ᶠ (n : ℕ) in atTop, a < ↑n
N : ℕ
hN : ∫ (x : ℝ) in Ici ↑N, ‖f' x‖ < ε
h'N : a < ↑N
x : ℝ
hx : x ≥ ↑N
⊢ IntervalIntegrable f' volume (↑N) x
Module: Mathlib.MeasureTheory.Function.Jacobian

Goal state before:
pp: E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : FiniteDimensional ℝ E
s : Set E
f : E → E
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
A : E →L[ℝ] E
δ : ℝ≥0
hf : ApproximatesLinearOn f A s δ
hs : MeasurableSet s
f' : E → E →L[ℝ] E
hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
x : E
hx : Tendsto (fun r ↦ μ (s ∩ closedBall x r) / μ (closedBall x r)) (𝓝[>] 0) (𝓝 1)
xs : x ∈ s
z : E
ε : ℝ
εpos : 0 < ε
B₁ : ∀ᶠ (r : ℝ) in 𝓝[>] 0, (s ∩ ({x} + r • closedBall z ε)).Nonempty
ρ : ℝ
ρpos : ρ > 0
hρ : ball x ρ ∩ s ⊆ {y | ‖f y - f x - (f' x) (y - x)‖ ≤ ε * ‖y - x‖}
B₂ : ∀ᶠ (r : ℝ) in 𝓝[>] 0, {x} + r • closedBall z ε ⊆ ball x ρ
r : ℝ
y : E
ys : y ∈ s
rρ : {x} + r • closedBall z ε ⊆ ball x ρ
rpos : 0 < r
hy : ∃ y_1 ∈ closedBall z ε, r • y_1 = -x + y
⊢ ∃ a ∈ closedBall z ε, y = x + r • a

Tactic:
rcases hy with ⟨a, az, ha⟩

Goal state after:
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : FiniteDimensional ℝ E
s : Set E
f : E → E
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
A : E →L[ℝ] E
δ : ℝ≥0
hf : ApproximatesLinearOn f A s δ
hs : MeasurableSet s
f' : E → E →L[ℝ] E
hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
x : E
hx : Tendsto (fun r ↦ μ (s ∩ closedBall x r) / μ (closedBall x r)) (𝓝[>] 0) (𝓝 1)
xs : x ∈ s
z : E
ε : ℝ
εpos : 0 < ε
B₁ : ∀ᶠ (r : ℝ) in 𝓝[>] 0, (s ∩ ({x} + r • closedBall z ε)).Nonempty
ρ : ℝ
ρpos : ρ > 0
hρ : ball x ρ ∩ s ⊆ {y | ‖f y - f x - (f' x) (y - x)‖ ≤ ε * ‖y - x‖}
B₂ : ∀ᶠ (r : ℝ) in 𝓝[>] 0, {x} + r • closedBall z ε ⊆ ball x ρ
r : ℝ
y : E
ys : y ∈ s
rρ : {x} + r • closedBall z ε ⊆ ball x ρ
rpos : 0 < r
a : E
az : a ∈ closedBall z ε
ha : r • a = -x + y
⊢ ∃ a ∈ closedBall z ε, y = x + r • a
Module: Mathlib.Analysis.Calculus.LineDeriv.Measurable

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : LocallyCompactSpace 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
inst✝⁶ : MeasurableSpace E
inst✝⁵ : OpensMeasurableSpace E
F : Type u_3
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace 𝕜 F
inst✝² : CompleteSpace F
f : E → F
v : E
inst✝¹ : MeasurableSpace F
inst✝ : BorelSpace F
hf : Continuous f
this✝¹ : MeasurableSpace 𝕜 := borel 𝕜
this✝ : BorelSpace 𝕜
g : E → 𝕜 → F := fun x t ↦ f (x + t • v)
hg : Continuous (Function.uncurry g)
⊢ Measurable fun x ↦ lineDeriv 𝕜 f x v

Tactic:
exact (measurable_deriv_with_param hg).comp measurable_prodMk_right

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntegralEqImproper

Goal state before:
pp: E : Type u_1
f : ℝ → E
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
hf : ContDiff ℝ 1 f
h2f : HasCompactSupport f
b : ℝ
⊢ ∫ (x : ℝ) in Iic b, deriv f x = f b

Tactic:
have := fun x (_ : x ∈ Iio b) ↦ hf.differentiable one_ne_zero x |>.hasDerivAt
  rw [integral_Iic_of_hasDerivAt_of_tendsto hf.continuous.continuousWithinAt this, sub_zero]
  · refine hf.continuous_deriv le_rfl |>.integrable_of_hasCompactSupport h2f.deriv |>.integrableOn
  rw [hasCompactSupport_iff_eventuallyEq, Filter.coclosedCompact_eq_cocompact] at h2f
  exact h2f.filter_mono _root_.atBot_le_cocompact |>.tendsto

Goal state after: