mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Analysis.Convolution

Goal state before:
pp: 𝕜 : Type u𝕜
G : Type uG
E : Type uE
E' : Type uE'
F : Type uF
inst✝¹³ : NormedAddCommGroup E
inst✝¹² : NormedAddCommGroup E'
inst✝¹¹ : NormedAddCommGroup F
f : G → E
g : G → E'
x : G
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NormedSpace 𝕜 E
inst✝⁸ : NormedSpace 𝕜 E'
inst✝⁷ : NormedSpace 𝕜 F
L : E →L[𝕜] E' →L[𝕜] F
inst✝⁶ : MeasurableSpace G
μ : Measure G
inst✝⁵ : NormedSpace ℝ F
inst✝⁴ : AddCommGroup G
inst✝³ : μ.IsAddLeftInvariant
inst✝² : μ.IsNegInvariant
inst✝¹ : MeasurableNeg G
inst✝ : MeasurableAdd G
h1 : ∀ᵐ (x : G) ∂μ, f (-x) = f x
h2 : ∀ᵐ (x : G) ∂μ, g (-x) = g x
⊢ ∫ (t : G), (L (f (-t))) (g (x + t)) ∂μ = ∫ (t : G), (L (f t)) (g (x - t)) ∂μ

Tactic:
rw [← integral_neg_eq_self]

Goal state after:
𝕜 : Type u𝕜
G : Type uG
E : Type uE
E' : Type uE'
F : Type uF
inst✝¹³ : NormedAddCommGroup E
inst✝¹² : NormedAddCommGroup E'
inst✝¹¹ : NormedAddCommGroup F
f : G → E
g : G → E'
x : G
inst✝¹⁰ : NontriviallyNormedField 𝕜
inst✝⁹ : NormedSpace 𝕜 E
inst✝⁸ : NormedSpace 𝕜 E'
inst✝⁷ : NormedSpace 𝕜 F
L : E →L[𝕜] E' →L[𝕜] F
inst✝⁶ : MeasurableSpace G
μ : Measure G
inst✝⁵ : NormedSpace ℝ F
inst✝⁴ : AddCommGroup G
inst✝³ : μ.IsAddLeftInvariant
inst✝² : μ.IsNegInvariant
inst✝¹ : MeasurableNeg G
inst✝ : MeasurableAdd G
h1 : ∀ᵐ (x : G) ∂μ, f (-x) = f x
h2 : ∀ᵐ (x : G) ∂μ, g (-x) = g x
⊢ ∫ (x_1 : G), (L (f (- -x_1))) (g (x + -x_1)) ∂μ = ∫ (t : G), (L (f t)) (g (x - t)) ∂μ
Module: Mathlib.Topology.MetricSpace.ProperSpace.Lemmas

Goal state before:
pp: α : Type u_1
inst✝ : PseudoMetricSpace α
⊢ ProperSpace α ↔ ∀ (x : α), IsProperMap (dist x)

Tactic:
refine ⟨fun _ ↦ isProperMap_dist, fun H ↦ ⟨fun x r ↦ ?_⟩⟩

Goal state after:
α : Type u_1
inst✝ : PseudoMetricSpace α
H : ∀ (x : α), IsProperMap (dist x)
x : α
r : ℝ
⊢ IsCompact (closedBall x r)
Module: Mathlib.MeasureTheory.Measure.Haar.NormedSpace

Goal state before:
pp: F : Type u_2
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
g : ℝ → F
a : ℝ
⊢ ∫ (x : ℝ), g (x * a⁻¹) = |a| • ∫ (y : ℝ), g y

Tactic:
by
  simpa only [mul_comm] using integral_comp_inv_mul_left g a

Goal state after:
Module: Mathlib.Analysis.Calculus.BumpFunction.FiniteDimension

Goal state before:
pp: E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Set E
x : E
n : ℕ∞
hs : s ∈ 𝓝 x
d : ℝ
d_pos : 0 < d
hd : Euclidean.closedBall x d ⊆ s
c : ContDiffBump (toEuclidean x) := { rIn := d / 2, rOut := d, rIn_pos := ⋯, rIn_lt_rOut := ⋯ }
f : E → ℝ := ↑c ∘ ⇑toEuclidean
f_supp : support f ⊆ Euclidean.ball x d
⊢ tsupport f ⊆ Euclidean.closedBall x d

Tactic:
rw [tsupport, ← Euclidean.closure_ball _ d_pos.ne']

Goal state after:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Set E
x : E
n : ℕ∞
hs : s ∈ 𝓝 x
d : ℝ
d_pos : 0 < d
hd : Euclidean.closedBall x d ⊆ s
c : ContDiffBump (toEuclidean x) := { rIn := d / 2, rOut := d, rIn_pos := ⋯, rIn_lt_rOut := ⋯ }
f : E → ℝ := ↑c ∘ ⇑toEuclidean
f_supp : support f ⊆ Euclidean.ball x d
⊢ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (support f) ⊆
    closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (Euclidean.ball x d)
Module: Mathlib.Analysis.Convolution

Goal state before:
pp: E : Type uE
E' : Type uE'
F : Type uF
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedAddCommGroup E'
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace ℝ E
inst✝² : NormedSpace ℝ E'
inst✝¹ : NormedSpace ℝ F
f : ℝ → E
g : ℝ → E'
L : E →L[ℝ] E' →L[ℝ] F
ν : Measure ℝ
inst✝ : NullSingletonClass ν
x : ℝ
h : x ∉ Ioi 0
t : ℝ
ht : 0 < t
⊢ x - t ∉ Ioi 0

Tactic:
rw [notMem_Ioi] at h ⊢

Goal state after:
E : Type uE
E' : Type uE'
F : Type uF
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedAddCommGroup E'
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace ℝ E
inst✝² : NormedSpace ℝ E'
inst✝¹ : NormedSpace ℝ F
f : ℝ → E
g : ℝ → E'
L : E →L[ℝ] E' →L[ℝ] F
ν : Measure ℝ
inst✝ : NullSingletonClass ν
x : ℝ
h : x ≤ 0
t : ℝ
ht : 0 < t
⊢ x - t ≤ 0
Module: Mathlib.MeasureTheory.Measure.Haar.Unique

Goal state before:
pp: case pos
G : Type u_1
inst✝⁹ : TopologicalSpace G
inst✝⁸ : Group G
inst✝⁷ : IsTopologicalGroup G
inst✝⁶ : MeasurableSpace G
inst✝⁵ : BorelSpace G
μ ν : Measure G
inst✝⁴ : IsFiniteMeasureOnCompacts μ
inst✝³ : IsFiniteMeasureOnCompacts ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : ν.IsMulRightInvariant
inst✝ : ν.IsOpenPosMeasure
f g : G → ℝ
hf : Continuous[inst✝⁹, _] f
h'f : HasCompactSupport f
hg : Continuous[inst✝⁹, _] g
h'g : HasCompactSupport g
g_nonneg : 0 ≤ g
x₀ : G
g_pos : g x₀ ≠ 0
Hf : LocallyCompactSpace G
D : G → ℝ := fun x ↦ ∫ (y : G), g (y⁻¹ * x) ∂ν
D_cont : Continuous[inst✝⁹, _] D
D_pos : ∀ (x : G), 0 < D x
K : Set G := tsupport f
K_comp : IsCompact K
L : Set G := tsupport g
L_comp : IsCompact L
M : Set G := (fun p ↦ p.1 * p.2⁻¹) '' K ×ˢ L
M_comp : IsCompact M
M'_comp : IsCompact (closure[inst✝⁹] M)
x y : G
hxy : (x, y) ∉ L ×ˢ closure[inst✝⁹] M
H : x ∈ L
⊢ f ((x, y).2 * (x, y).1) * (D ((x, y).2 * (x, y).1))⁻¹ * g (x, y).1 = 0

Tactic:
have : f (y * x) = 0 := by
            apply image_eq_zero_of_notMem_tsupport
            contrapose hxy
            simp only [mem_prod, H, true_and]
            apply subset_closure
            simp only [M, mem_image, mem_prod, Prod.exists]
            exact ⟨y * x, x, ⟨hxy, H⟩, by group⟩

Goal state after:
case pos
G : Type u_1
inst✝⁹ : TopologicalSpace G
inst✝⁸ : Group G
inst✝⁷ : IsTopologicalGroup G
inst✝⁶ : MeasurableSpace G
inst✝⁵ : BorelSpace G
μ ν : Measure G
inst✝⁴ : IsFiniteMeasureOnCompacts μ
inst✝³ : IsFiniteMeasureOnCompacts ν
inst✝² : μ.IsMulLeftInvariant
inst✝¹ : ν.IsMulRightInvariant
inst✝ : ν.IsOpenPosMeasure
f g : G → ℝ
hf : Continuous[inst✝⁹, _] f
h'f : HasCompactSupport f
hg : Continuous[inst✝⁹, _] g
h'g : HasCompactSupport g
g_nonneg : 0 ≤ g
x₀ : G
g_pos : g x₀ ≠ 0
Hf : LocallyCompactSpace G
D : G → ℝ := fun x ↦ ∫ (y : G), g (y⁻¹ * x) ∂ν
D_cont : Continuous[inst✝⁹, _] D
D_pos : ∀ (x : G), 0 < D x
K : Set G := tsupport f
K_comp : IsCompact K
L : Set G := tsupport g
L_comp : IsCompact L
M : Set G := (fun p ↦ p.1 * p.2⁻¹) '' K ×ˢ L
M_comp : IsCompact M
M'_comp : IsCompact (closure[inst✝⁹] M)
x y : G
hxy : (x, y) ∉ L ×ˢ closure[inst✝⁹] M
H : x ∈ L
this : f (y * x) = 0
⊢ f ((x, y).2 * (x, y).1) * (D ((x, y).2 * (x, y).1))⁻¹ * g (x, y).1 = 0
Module: Mathlib.Analysis.Calculus.BumpFunction.FiniteDimension

Goal state before:
pp: E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
D : ℝ
x : E
⊢ 0 ≤ |D| ^ finrank ℝ E

Tactic:
apply pow_nonneg (abs_nonneg D)

Goal state after:
Module: Mathlib.Analysis.Calculus.BumpFunction.FiniteDimension

Goal state before:
pp: E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
D : ℝ
x : E
Dpos : 0 < D
D_lt_one : D < 1
hx : ‖x‖ < 1 + D
z : E := ⋯
hz : z = (D / (1 + D)) • x
B : 0 < 1 + D
C : ball z (D * (1 + D - ‖x‖) / (1 + D)) ⊆ support fun y ↦ w D y * φ (x - y)
⊢ 0 < μ (ball z (D * (1 + D - ‖x‖) / (1 + D)))

Tactic:
apply measure_ball_pos

Goal state after:
E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
D : ℝ
x : E
Dpos : 0 < D
D_lt_one : D < 1
hx : ‖x‖ < 1 + D
z : E := ⋯
hz : z = (D / (1 + D)) • x
B : 0 < 1 + D
C : ball z (D * (1 + D - ‖x‖) / (1 + D)) ⊆ support fun y ↦ w D y * φ (x - y)
⊢ 0 < D * (1 + D - ‖x‖) / (1 + D)
Module: Mathlib.Analysis.Calculus.BumpFunction.FiniteDimension

Goal state before:
pp: E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
⊢ ContDiffOn ℝ ∞ (uncurry y) (Ioo 0 1 ×ˢ univ)

Tactic:
have hs : IsOpen (Ioo (0 : ℝ) (1 : ℝ)) := isOpen_Ioo

Goal state after:
E : Type u_1
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℝ E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : MeasurableSpace E
inst✝ : BorelSpace E
hs : IsOpen (Ioo 0 1)
⊢ ContDiffOn ℝ ∞ (uncurry y) (Ioo 0 1 ×ˢ univ)
Module: Mathlib.Analysis.Calculus.BumpFunction.Convolution

Goal state before:
pp: G : Type uG
E' : Type uE'
inst✝⁸ : NormedAddCommGroup E'
g : G → E'
inst✝⁷ : MeasurableSpace G
μ : Measure G
inst✝⁶ : NormedSpace ℝ E'
inst✝⁵ : NormedAddCommGroup G
inst✝⁴ : NormedSpace ℝ G
inst✝³ : CompleteSpace E'
inst✝² : BorelSpace G
inst✝¹ : FiniteDimensional ℝ G
inst✝ : μ.IsAddHaarMeasure
ι : Type u_1
φ : ι → ContDiffBump 0
l : Filter ι
K : ℝ
hφ : Tendsto (fun i ↦ (φ i).rOut) l (𝓝 0)
h'φ : ∀ᶠ (i : ι) in l, (φ i).rOut ≤ K * (φ i).rIn
hg : LocallyIntegrable g μ
x₀ : G
h₀ : Tendsto (fun a ↦ ⨍ (y : G) in a, ‖g y - g x₀‖ ∂μ) ((Besicovitch.vitaliFamily μ).filterAt x₀) (𝓝 0)
hφ' : Tendsto (fun i ↦ (φ i).rOut) l (𝓝[>] 0)
this : Tendsto (((fun a ↦ ⨍ (y : G) in a, ‖g y - g x₀‖ ∂μ) ∘ fun r ↦ closedBall x₀ r) ∘ fun i ↦ (φ i).rOut) l (𝓝 0)
i : ι
⊢ 1 = ∫ (y : G), (φ i).normed μ (x₀ - y) ∂μ

Tactic:
rw [← integral_neg_eq_self]

Goal state after:
G : Type uG
E' : Type uE'
inst✝⁸ : NormedAddCommGroup E'
g : G → E'
inst✝⁷ : MeasurableSpace G
μ : Measure G
inst✝⁶ : NormedSpace ℝ E'
inst✝⁵ : NormedAddCommGroup G
inst✝⁴ : NormedSpace ℝ G
inst✝³ : CompleteSpace E'
inst✝² : BorelSpace G
inst✝¹ : FiniteDimensional ℝ G
inst✝ : μ.IsAddHaarMeasure
ι : Type u_1
φ : ι → ContDiffBump 0
l : Filter ι
K : ℝ
hφ : Tendsto (fun i ↦ (φ i).rOut) l (𝓝 0)
h'φ : ∀ᶠ (i : ι) in l, (φ i).rOut ≤ K * (φ i).rIn
hg : LocallyIntegrable g μ
x₀ : G
h₀ : Tendsto (fun a ↦ ⨍ (y : G) in a, ‖g y - g x₀‖ ∂μ) ((Besicovitch.vitaliFamily μ).filterAt x₀) (𝓝 0)
hφ' : Tendsto (fun i ↦ (φ i).rOut) l (𝓝[>] 0)
this : Tendsto (((fun a ↦ ⨍ (y : G) in a, ‖g y - g x₀‖ ∂μ) ∘ fun r ↦ closedBall x₀ r) ∘ fun i ↦ (φ i).rOut) l (𝓝 0)
i : ι
⊢ 1 = ∫ (x : G), (φ i).normed μ (x₀ - -x) ∂μ
Module: Mathlib.MeasureTheory.Covering.BesicovitchVectorSpace

Goal state before:
pp: case inl
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
h :
  ∀ (δ : ℝ),
    0 < δ → δ < 1 → ∃ s, (∀ c ∈ s, ‖c‖ ≤ 2) ∧ (∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 - δ ≤ ‖c - d‖) ∧ multiplicity E < s.card
N : ℕ := multiplicity E + 1
hN : N = multiplicity E + 1
δ : ℝ
hδ : 0 < δ
hδ' : δ < 1
⊢ ∃ f, (∀ (i : Fin N), ‖f i‖ ≤ 2) ∧ Pairwise fun i j ↦ 1 - δ ≤ ‖f i - f j‖

Tactic:
rcases h δ hδ hδ' with ⟨s, hs, h's, s_card⟩

Goal state after:
case inl
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
h :
  ∀ (δ : ℝ),
    0 < δ → δ < 1 → ∃ s, (∀ c ∈ s, ‖c‖ ≤ 2) ∧ (∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 - δ ≤ ‖c - d‖) ∧ multiplicity E < s.card
N : ℕ := multiplicity E + 1
hN : N = multiplicity E + 1
δ : ℝ
hδ : 0 < δ
hδ' : δ < 1
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h's : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 - δ ≤ ‖c - d‖
s_card : multiplicity E < s.card
⊢ ∃ f, (∀ (i : Fin N), ‖f i‖ ≤ 2) ∧ Pairwise fun i j ↦ 1 - δ ≤ ‖f i - f j‖
Module: Mathlib.MeasureTheory.Measure.Haar.Unique

Goal state before:
pp: case pos
G : Type u_1
inst✝⁷ : TopologicalSpace G
inst✝⁶ : Group G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : MeasurableSpace G
inst✝³ : BorelSpace G
inst✝² : LocallyCompactSpace G
μ' μ : Measure G
inst✝¹ : μ.IsHaarMeasure
inst✝ : μ'.IsHaarMeasure
s : Set G
hs : MeasurableSet s
h's : μ.IsEverywherePos s
ν : Measure G := μ'.haarScalarFactor μ • μ
k : Set G
k_comp : IsCompact k
k_closed : IsClosed[inst✝⁷] k
k_mem : k ∈ 𝓝 1
one_k : 1 ∈ k
A : Set (Set G) := {t | t ⊆ s ∧ t.PairwiseDisjoint fun x ↦ x • k}
f : ℕ → G
m_max : Maximal (fun x ↦ x ∈ A) (range f)
hms : range f ⊆ s
hdj : (range f).PairwiseDisjoint fun x ↦ x • k
hm : (range f).Nonempty
h'm : (range f).Countable
M : ∀ (i : ℕ), MeasurableSet (disjointed (fun n ↦ s ∩ f n • (k * k⁻¹)) i)
sm : s ⊆ ⋃ y, f y • (k * k⁻¹)
s_eq : s = ⋃ n, s ∩ f n • (k * k⁻¹)
⊢ μ' s = ν s

Tactic:
have I : μ' s = ∑' n, μ' (disjointed (fun n ↦ s ∩ f n • (k * k⁻¹)) n) := by
      rw [← measure_iUnion (disjoint_disjointed _) M, iUnion_disjointed, ← s_eq]

Goal state after:
case pos
G : Type u_1
inst✝⁷ : TopologicalSpace G
inst✝⁶ : Group G
inst✝⁵ : IsTopologicalGroup G
inst✝⁴ : MeasurableSpace G
inst✝³ : BorelSpace G
inst✝² : LocallyCompactSpace G
μ' μ : Measure G
inst✝¹ : μ.IsHaarMeasure
inst✝ : μ'.IsHaarMeasure
s : Set G
hs : MeasurableSet s
h's : μ.IsEverywherePos s
ν : Measure G := μ'.haarScalarFactor μ • μ
k : Set G
k_comp : IsCompact k
k_closed : IsClosed[inst✝⁷] k
k_mem : k ∈ 𝓝 1
one_k : 1 ∈ k
A : Set (Set G) := {t | t ⊆ s ∧ t.PairwiseDisjoint fun x ↦ x • k}
f : ℕ → G
m_max : Maximal (fun x ↦ x ∈ A) (range f)
hms : range f ⊆ s
hdj : (range f).PairwiseDisjoint fun x ↦ x • k
hm : (range f).Nonempty
h'm : (range f).Countable
M : ∀ (i : ℕ), MeasurableSet (disjointed (fun n ↦ s ∩ f n • (k * k⁻¹)) i)
sm : s ⊆ ⋃ y, f y • (k * k⁻¹)
s_eq : s = ⋃ n, s ∩ f n • (k * k⁻¹)
I : μ' s = ∑' (n : ℕ), μ' (disjointed (fun n ↦ s ∩ f n • (k * k⁻¹)) n)
⊢ μ' s = ν s
Module: Mathlib.Analysis.Calculus.Deriv.Abs

Goal state before:
pp: E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : E → ℝ
f' : StrongDual ℝ E
x : E
hf : HasFDerivAt f f' x
h₀ : f x ≠ 0
⊢ HasFDerivAt (fun x ↦ |f x|) (↑(SignType.sign (f x)) • f') x

Tactic:
by
  convert! (hasDerivAt_abs h₀).hasFDerivAt.comp x hf using 1
  ext y
  simp [mul_comm]

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

Goal state before:
pp: case refine_3
α : Type u_1
inst✝⁵ : MetricSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : MeasurableSpace α
inst✝² : OpensMeasurableSpace α
inst✝¹ : HasBesicovitchCovering α
μ : Measure α
inst✝ : IsFiniteMeasure μ
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
N : ℕ
τ : ℝ
hτ : 1 < τ
hN : IsEmpty (SatelliteConfig α N τ)
P : Finset (α × ℝ) → Prop :=
  fun t ↦ ((↑t).PairwiseDisjoint fun p ↦ closedBall p.1 p.2) ∧ (∀ p ∈ t, p.1 ∈ s) ∧ ∀ p ∈ t, p.2 ∈ f p.1
F : Finset (α × ℝ) → Finset (α × ℝ)
hF :
  ∀ (t : Finset (α × ℝ)),
    P t →
      t ⊆ F t ∧ P (F t) ∧ μ (s \ ⋃ p ∈ F t, closedBall p.1 p.2) ≤ ↑N / (↑N + 1) * μ (s \ ⋃ p ∈ t, closedBall p.1 p.2)
u : ℕ → Finset (α × ℝ) := fun n ↦ F^[n] ∅
u_succ : ∀ (n : ℕ), u n.succ = F (u n)
Pu : ∀ (n : ℕ), P (u n)
⊢ μ (s \ ⋃ p ∈ ⋃ n, ↑(u n), closedBall p.1 p.2) = 0

Tactic:
have A :
      ∀ n,
        μ (s \ ⋃ (p : α × ℝ) (_ : p ∈ ⋃ n : ℕ, (u n : Set (α × ℝ))), closedBall p.fst p.snd) ≤
          μ (s \ ⋃ (p : α × ℝ) (_ : p ∈ u n), closedBall p.fst p.snd) := by
      intro n
      gcongr μ (s \ ?_)
      exact biUnion_subset_biUnion_left (subset_iUnion (fun i => (u i : Set (α × ℝ))) n)

Goal state after:
case refine_3
α : Type u_1
inst✝⁵ : MetricSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : MeasurableSpace α
inst✝² : OpensMeasurableSpace α
inst✝¹ : HasBesicovitchCovering α
μ : Measure α
inst✝ : IsFiniteMeasure μ
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
N : ℕ
τ : ℝ
hτ : 1 < τ
hN : IsEmpty (SatelliteConfig α N τ)
P : Finset (α × ℝ) → Prop :=
  fun t ↦ ((↑t).PairwiseDisjoint fun p ↦ closedBall p.1 p.2) ∧ (∀ p ∈ t, p.1 ∈ s) ∧ ∀ p ∈ t, p.2 ∈ f p.1
F : Finset (α × ℝ) → Finset (α × ℝ)
hF :
  ∀ (t : Finset (α × ℝ)),
    P t →
      t ⊆ F t ∧ P (F t) ∧ μ (s \ ⋃ p ∈ F t, closedBall p.1 p.2) ≤ ↑N / (↑N + 1) * μ (s \ ⋃ p ∈ t, closedBall p.1 p.2)
u : ℕ → Finset (α × ℝ) := fun n ↦ F^[n] ∅
u_succ : ∀ (n : ℕ), u n.succ = F (u n)
Pu : ∀ (n : ℕ), P (u n)
A : ∀ (n : ℕ), μ (s \ ⋃ p ∈ ⋃ n, ↑(u n), closedBall p.1 p.2) ≤ μ (s \ ⋃ p ∈ u n, closedBall p.1 p.2)
⊢ μ (s \ ⋃ p ∈ ⋃ n, ↑(u n), closedBall p.1 p.2) = 0
Module: Mathlib.MeasureTheory.Covering.Besicovitch

Goal state before:
pp: α : Type u_1
inst✝⁵ : MetricSpace α
inst✝⁴ : SecondCountableTopology α
inst✝³ : MeasurableSpace α
inst✝² : OpensMeasurableSpace α
inst✝¹ : HasBesicovitchCovering α
μ : Measure α
inst✝ : IsFiniteMeasure μ
f : α → Set ℝ
s : Set α
hf : ∀ x ∈ s, ∀ δ > 0, (f x ∩ Ioo 0 δ).Nonempty
N : ℕ
τ : ℝ
hτ : 1 < τ
hN : IsEmpty (SatelliteConfig α N τ)
P : Finset (α × ℝ) → Prop :=
  fun t ↦ ((↑t).PairwiseDisjoint fun p ↦ closedBall p.1 p.2) ∧ (∀ p ∈ t, p.1 ∈ s) ∧ ∀ p ∈ t, p.2 ∈ f p.1
F : Finset (α × ℝ) → Finset (α × ℝ)
hF :
  ∀ (t : Finset (α × ℝ)),
    P t →
      t ⊆ F t ∧ P (F t) ∧ μ (s \ ⋃ p ∈ F t, closedBall p.1 p.2) ≤ ↑N / (↑N + 1) * μ (s \ ⋃ p ∈ t, closedBall p.1 p.2)
u : ℕ → Finset (α × ℝ) := fun n ↦ F^[n] ∅
u_succ : ∀ (n : ℕ), u n.succ = F (u n)
Pu : ∀ (n : ℕ), P (u n)
A : ∀ (n : ℕ), μ (s \ ⋃ p ∈ ⋃ n, ↑(u n), closedBall p.1 p.2) ≤ μ (s \ ⋃ p ∈ u n, closedBall p.1 p.2)
n : ℕ
IH : μ (s \ ⋃ p ∈ u n, closedBall p.1 p.2) ≤ (↑N / (↑N + 1)) ^ n * μ s
⊢ μ (s \ ⋃ p ∈ F (u n), closedBall p.1 p.2) ≤ ↑N / (↑N + 1) * μ (s \ ⋃ p ∈ u n, closedBall p.1 p.2)

Tactic:
exact (hF (u n) (Pu n)).2.2

Goal state after:
Module: Mathlib.Analysis.Normed.Module.Alternating.Uncurry.Fin

Goal state before:
pp: 𝕜 : Type u_1
E : Type u_2
F : Type u_3
G : Type u_4
inst✝⁶ : NontriviallyNormedField 𝕜
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace 𝕜 F
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace 𝕜 G
n : ℕ
f : F [⋀^Fin (n + 1)]→L[𝕜] G
g : E →L[𝕜] F
⊢ f.fderivCompContinuousLinearMap g =
    alternatizeUncurryFinCLM 𝕜 E G ∘SL ContinuousLinearMap.postcomp E (compContinuousLinearMapCLM g ∘SL f.curryLeft)

Tactic:
ext dg v
  have (i j : Fin (n + 1)) :
      i.insertNth (α := fun _ ↦ E →L[𝕜] F) dg (fun _ ↦ g) j (v j) =
        i.insertNth (α := fun _ ↦ F) (dg (v i)) (g ∘ i.removeNth v) j := by
    cases j using i.succAboveCases <;> simp [Fin.removeNth]
  simp [alternatizeUncurryFin_apply, ← Fin.insertNth_removeNth, Fin.removeNth_fun_const,
    ← map_insertNth, this]

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

Goal state before:
pp: 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)),
    (∀ x ∈ s, f x ⊆ (fun r ↦ closedBall x r) '' Ioi 0) →
      (∀ x ∈ s, ∀ ε > 0, ∃ t ∈ f x, t ⊆ closedBall x ε) →
        ∃ t, (∀ p ∈ t, p.1 ∈ s) ∧ (t.PairwiseDisjoint fun p ↦ p.2) ∧ (∀ p ∈ t, p.2 ∈ f p.1) ∧ μ (s \ ⋃ p ∈ t, p.2) = 0

Tactic:
f

Goal state after:
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)
⊢ (∀ x ∈ s, f x ⊆ (fun r ↦ closedBall x r) '' Ioi 0) →
    (∀ x ∈ s, ∀ ε > 0, ∃ t ∈ f x, t ⊆ closedBall x ε) →
      ∃ t, (∀ p ∈ t, p.1 ∈ s) ∧ (t.PairwiseDisjoint fun p ↦ p.2) ∧ (∀ p ∈ t, p.2 ∈ f p.1) ∧ μ (s \ ⋃ p ∈ t, p.2) = 0
Module: Mathlib.Analysis.Calculus.FDeriv.Norm

Goal state before:
pp: E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x : E
h : DifferentiableAt ℝ (fun x ↦ ‖x‖) x
this : ∀ (t : ℝ), ‖x + t • x‖ = |1 + t| * ‖x‖
⊢ deriv (_root_.abs ∘ fun t ↦ 1 + t) 0 * ‖x‖ = ‖x‖

Tactic:
deriv_comp,

Goal state after:
E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x : E
h : DifferentiableAt ℝ (fun x ↦ ‖x‖) x
this : ∀ (t : ℝ), ‖x + t • x‖ = |1 + t| * ‖x‖
⊢ deriv _root_.abs (1 + 0) * deriv (fun t ↦ 1 + t) 0 * ‖x‖ = ‖x‖

case hh₂
E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x : E
h : DifferentiableAt ℝ (fun x ↦ ‖x‖) x
this : ∀ (t : ℝ), ‖x + t • x‖ = |1 + t| * ‖x‖
⊢ DifferentiableAt ℝ _root_.abs (1 + 0)

case hh
E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x : E
h : DifferentiableAt ℝ (fun x ↦ ‖x‖) x
this : ∀ (t : ℝ), ‖x + t • x‖ = |1 + t| * ‖x‖
⊢ DifferentiableAt ℝ (fun t ↦ 1 + t) 0
Module: Mathlib.Analysis.Calculus.ImplicitFunction.ProdDomain

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E₁ : Type u_2
inst✝⁸ : NormedAddCommGroup E₁
inst✝⁷ : NormedSpace 𝕜 E₁
inst✝⁶ : CompleteSpace E₁
E₂ : Type u_3
inst✝⁵ : NormedAddCommGroup E₂
inst✝⁴ : NormedSpace 𝕜 E₂
inst✝³ : CompleteSpace E₂
F : Type u_4
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace 𝕜 F
inst✝ : CompleteSpace F
u : E₁ × E₂
f : E₁ × E₂ → F
f'u : E₁ × E₂ →L[𝕜] F
dfu : HasStrictFDerivAt f f'u u
if₂u : (f'u ∘SL ContinuousLinearMap.inr 𝕜 E₁ E₂).IsInvertible
⊢ ∀ᶠ (v : E₁ × E₂) in 𝓝 u, f v = f u ↔ dfu.implicitFunctionOfProdDomain if₂u v.1 = v.2

Tactic:
by
  let φ := dfu.implicitFunctionDataOfProdDomain if₂u
  filter_upwards [φ.leftFun_eq_iff_implicitFunction, φ.rightFun_implicitFunction_eq_rightFun]
  exact fun v h _ => Iff.trans h ⟨congrArg _, by aesop⟩

Goal state after:
Module: Mathlib.Analysis.Calculus.ImplicitContDiff

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁹ : RCLike 𝕜
E₁ : Type u_2
inst✝⁸ : NormedAddCommGroup E₁
inst✝⁷ : NormedSpace 𝕜 E₁
inst✝⁶ : CompleteSpace E₁
E₂ : Type u_3
inst✝⁵ : NormedAddCommGroup E₂
inst✝⁴ : NormedSpace 𝕜 E₂
inst✝³ : CompleteSpace E₂
F : Type u_4
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace 𝕜 F
inst✝ : CompleteSpace F
u : E₁ × E₂
f : E₁ × E₂ → F
n : ℕ∞ω
cdf : ContDiffAt 𝕜 n f u
pn : n ≠ 0
if₂ : (fderiv 𝕜 f u ∘SL ContinuousLinearMap.inr 𝕜 E₁ E₂).IsInvertible
φ : ImplicitFunctionData 𝕜 (E₁ × E₂) F E₁ := ⋯.implicitFunctionDataOfProdDomain if₂
⊢ ContDiffAt 𝕜 n φ.leftFun φ.pt

Tactic:
by simpa [φ] using cdf

Goal state after:
Module: Mathlib.Analysis.Calculus.Implicit

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁸ : NormedAddCommGroup E
inst✝⁷ : NormedSpace 𝕜 E
inst✝⁶ : CompleteSpace E
F : Type u_3
inst✝⁵ : NormedAddCommGroup F
inst✝⁴ : NormedSpace 𝕜 F
inst✝³ : CompleteSpace F
G : Type u_4
inst✝² : NormedAddCommGroup G
inst✝¹ : NormedSpace 𝕜 G
inst✝ : CompleteSpace G
φ : ImplicitFunctionData 𝕜 E F G
⊢ ∀ᶠ (x : E) in 𝓝 φ.pt, φ.leftFun x = φ.leftFun φ.pt ↔ φ.implicitFunction (φ.leftFun φ.pt) (φ.rightFun x) = x

Tactic:
by
  filter_upwards [φ.implicitFunction_apply_image, φ.leftFun_implicitFunction_eq_leftFun] with x _ _
  constructor <;> exact fun h => by rwa [← h]

Goal state after:
Module: Mathlib.Analysis.Calculus.LHopital

Goal state before:
pp: case refine_2
a : ℝ
l : Filter ℝ
f g : ℝ → ℝ
s : Set ℝ
hs : Convex ℝ s
hdf : ∀ᶠ (x : ℝ) in 𝓝[s \ {a}] a, DifferentiableAt ℝ f x
hg' : ∀ᶠ (x : ℝ) in 𝓝[s \ {a}] a, deriv g x ≠ 0
hfa : Tendsto f (𝓝[s \ {a}] a) (𝓝 0)
hga : Tendsto g (𝓝[s \ {a}] a) (𝓝 0)
hdiv : Tendsto (fun x ↦ deriv f x / deriv g x) (𝓝[s \ {a}] a) l
x✝ : ℝ
a✝ : s \ {a} ∈ 𝓝 x✝
⊢ (fun x ↦ deriv f x / deriv g x) x✝ = (fun x ↦ derivWithin f (s \ {a}) x / derivWithin g (s \ {a}) x) x✝

Tactic:
· simp only
    iterate 2 rw [derivWithin_of_mem_nhds ‹_›]

Goal state after:
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
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
A : E →L[ℝ] E
m : ℝ≥0
hm : ENNReal.ofReal |A.det| < ↑m
d : ℝ≥0∞ := ENNReal.ofReal |A.det|
ε : ℝ
hε : μ (closedBall 0 ε + ⇑A '' closedBall 0 1) < ↑m * μ (closedBall 0 1)
εpos : 0 < ε
this : Iio (NNReal.mk ε ⋯) ∈ 𝓝 0
δ : ℝ≥0
hδ : δ ∈ Iio (NNReal.mk ε ⋯)
s : Set E
⊢ ∀ (f : E → E), ApproximatesLinearOn f A s δ → μ (f '' s) ≤ ↑m * μ s

Tactic:
f

Goal state after:
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : FiniteDimensional ℝ E
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
μ : Measure E
inst✝ : μ.IsAddHaarMeasure
A : E →L[ℝ] E
m : ℝ≥0
hm : ENNReal.ofReal |A.det| < ↑m
d : ℝ≥0∞ := ENNReal.ofReal |A.det|
ε : ℝ
hε : μ (closedBall 0 ε + ⇑A '' closedBall 0 1) < ↑m * μ (closedBall 0 1)
εpos : 0 < ε
this : Iio (NNReal.mk ε ⋯) ∈ 𝓝 0
δ : ℝ≥0
hδ : δ ∈ Iio (NNReal.mk ε ⋯)
s : Set E
f : E → E
⊢ ApproximatesLinearOn f A s δ → μ (f '' s) ≤ ↑m * μ s
Module: Mathlib.MeasureTheory.Function.JacobianOneDim

Goal state before:
pp: F : Type u_1
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f f' : ℝ → ℝ
a b : ℝ
g : ℝ → F
hf : ContinuousOn f (Icc a b)
hff' : ∀ x ∈ Ioo a b, HasDerivAt f (f' x) x
hf' : ∀ x ∈ Ioo a b, 0 ≤ f' x
hab : a ≤ b
M : MonotoneOn f (Icc a b)
⊢ volume (f '' Ioo a b \ f '' Icc a b) = 0

Tactic:
simp [show f '' Ioo a b \ f '' Icc a b = ∅ by grind]

Goal state after: