mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.MeasureTheory.Measure.Haar.Unique

Goal state before:
pp: case refine_1
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}
c : Set (Set G)
cA : c ⊆ A
hc : IsChain (fun x1 x2 ↦ x1 ⊆ x2) c
⊢ ∀ i ∈ c, i ⊆ s

Tactic:
intro a ac x hx

Goal state after:
case refine_1
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}
c : Set (Set G)
cA : c ⊆ A
hc : IsChain (fun x1 x2 ↦ x1 ⊆ x2) c
a : Set G
ac : a ∈ c
x : G
hx : x ∈ a
⊢ x ∈ s
Module: Mathlib.MeasureTheory.Measure.Haar.Unique

Goal state before:
pp: 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}
m : Set G
m_max : Maximal (fun x ↦ x ∈ A) m
hms : m ⊆ s
hdj : m.PairwiseDisjoint fun x ↦ x • k
sm : s ⊆ ⋃ x ∈ m, x • (k * k⁻¹)
hm : m.Nonempty
ρ : Measure G
hρ : ρ.IsEverywherePos s
M : ∀ (i : ↑m), MeasurableSet (s ∩ ↑i • k)
h'm : ρ s ≠ ∞
this : ∑' (x : ↑m), ρ (s ∩ ↑x • k) < ∞
C : (support fun i ↦ ρ (s ∩ ↑i • k)).Countable
⊢ (support fun i ↦ ρ (s ∩ ↑i • k)) = univ

Tactic:
refine eq_univ_iff_forall.2 fun i ↦ ?_

Goal state after:
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}
m : Set G
m_max : Maximal (fun x ↦ x ∈ A) m
hms : m ⊆ s
hdj : m.PairwiseDisjoint fun x ↦ x • k
sm : s ⊆ ⋃ x ∈ m, x • (k * k⁻¹)
hm : m.Nonempty
ρ : Measure G
hρ : ρ.IsEverywherePos s
M : ∀ (i : ↑m), MeasurableSet (s ∩ ↑i • k)
h'm : ρ s ≠ ∞
this : ∑' (x : ↑m), ρ (s ∩ ↑x • k) < ∞
C : (support fun i ↦ ρ (s ∩ ↑i • k)).Countable
i : ↑m
⊢ i ∈ support fun i ↦ ρ (s ∩ ↑i • k)
Module: Mathlib.MeasureTheory.Covering.BesicovitchVectorSpace

Goal state before:
pp: E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
N : ℕ
τ : ℝ
a : SatelliteConfig E N τ
lastc : a.c (last N) = 0
lastr : a.r (last N) = 1
hτ : 1 ≤ τ
δ : ℝ
hδ1 : τ ≤ 1 + δ / 4
hδ2 : δ ≤ 1
c' : Fin N.succ → E := fun i ↦ if ‖a.c i‖ ≤ 2 then a.c i else (2 / ‖a.c i‖) • a.c i
⊢ ∃ c', (∀ (n : Fin N.succ), ‖c' n‖ ≤ 2) ∧ Pairwise fun i j ↦ 1 - δ ≤ ‖c' i - c' j‖

Tactic:
have norm_c'_le : ∀ i, ‖c' i‖ ≤ 2 := by
    intro i
    simp only [c']
    split_ifs with h; · exact h
    by_cases hi : ‖a.c i‖ = 0 <;> simp [norm_smul, hi]

Goal state after:
E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
N : ℕ
τ : ℝ
a : SatelliteConfig E N τ
lastc : a.c (last N) = 0
lastr : a.r (last N) = 1
hτ : 1 ≤ τ
δ : ℝ
hδ1 : τ ≤ 1 + δ / 4
hδ2 : δ ≤ 1
c' : Fin N.succ → E := fun i ↦ if ‖a.c i‖ ≤ 2 then a.c i else (2 / ‖a.c i‖) • a.c i
norm_c'_le : ∀ (i : Fin N.succ), ‖c' i‖ ≤ 2
⊢ ∃ c', (∀ (n : Fin N.succ), ‖c' n‖ ≤ 2) ∧ Pairwise fun i j ↦ 1 - δ ≤ ‖c' i - c' j‖
Module: Mathlib.MeasureTheory.Covering.Besicovitch

Goal state before:
pp: case inr
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
t : Finset (α × ℝ)
ht : P t
B : Set α := ⋃ p ∈ t, closedBall p.1 p.2
hB✝ : B = ⋃ p ∈ t, closedBall p.1 p.2
B_closed : IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] B
s' : Set α := s \ B
x : α
hx : x ∈ s'
xs : x ∈ s
hB : B.Nonempty
r✝ : ℝ := infDist x B
this : 0 < min r✝ 1
r : ℝ
hr : r ∈ f x
h'r : r ∈ Ioo 0 (min r✝ 1)
⊢ Disjoint B (closedBall x r)

Tactic:
disjoint_comm

Goal state after:
case inr
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
t : Finset (α × ℝ)
ht : P t
B : Set α := ⋃ p ∈ t, closedBall p.1 p.2
hB✝ : B = ⋃ p ∈ t, closedBall p.1 p.2
B_closed : IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] B
s' : Set α := s \ B
x : α
hx : x ∈ s'
xs : x ∈ s
hB : B.Nonempty
r✝ : ℝ := infDist x B
this : 0 < min r✝ 1
r : ℝ
hr : r ∈ f x
h'r : r ∈ Ioo 0 (min r✝ 1)
⊢ Disjoint (closedBall x r) B
Module: Mathlib.Topology.MetricSpace.Holder

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : PseudoEMetricSpace X
inst✝ : PseudoEMetricSpace Y
f : X → Y
C : ℝ≥0
⊢ Convex ℝ≥0 {r | HolderWith C r f}

Tactic:
by
  simp_rw [← holderOnWith_univ]
  exact convex_setOfPred_holderOnWith f C _

Goal state after:
Module: Mathlib.Analysis.Calculus.ContDiffHolder.Pointwise

Goal state before:
pp: E : Type u_1
F : Type u_2
G : Type u_3
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace ℝ F
inst✝¹ : NormedAddCommGroup G
inst✝ : NormedSpace ℝ G
k : ℕ
α : ↑I
f : E → F
a : E
g : F → G
hg : ContDiffPointwiseHolderAt k α g (f a)
hf : ContDiffPointwiseHolderAt k α f a
hd : DifferentiableAt ℝ g (f a) ∨ DifferentiableAt ℝ f a
⊢ (fun x ↦ iteratedFDeriv ℝ k (g ∘ f) x - iteratedFDeriv ℝ k (g ∘ f) a) =ᶠ[𝓝 a] fun x ↦
    (ftaylorSeries ℝ g (f x)).taylorComp (ftaylorSeries ℝ f x) k -
      (ftaylorSeries ℝ g (f a)).taylorComp (ftaylorSeries ℝ f a) k

Tactic:
by
      filter_upwards [hf.contDiffAt.eventually (by simp),
        hf.continuousAt.eventually (hg.contDiffAt.eventually (by simp))] with x hfx hgx
      rw [iteratedFDeriv_comp hgx hfx le_rfl,
        iteratedFDeriv_comp hg.contDiffAt hf.contDiffAt le_rfl]

Goal state after:
Module: Mathlib.Analysis.Calculus.Deriv.Pi

Goal state before:
pp: case e'_9
𝕜 : Type u_1
ι : Type u_2
inst✝¹ : DecidableEq ι
inst✝ : NontriviallyNormedField 𝕜
x : ι → 𝕜
i : ι
y z : 𝕜
j : ι
⊢ Function.update 0 i z j = (ContinuousLinearMap.pi (Pi.single i (ContinuousLinearMap.id 𝕜 𝕜))) z j

Tactic:
Function.update_apply

Goal state after:
case e'_9
𝕜 : Type u_1
ι : Type u_2
inst✝¹ : DecidableEq ι
inst✝ : NontriviallyNormedField 𝕜
x : ι → 𝕜
i : ι
y z : 𝕜
j : ι
⊢ (if j = i then z else 0 j) = (ContinuousLinearMap.pi (Pi.single i (ContinuousLinearMap.id 𝕜 𝕜))) z j
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
s : Set E
ι : Type u_2
A' : Type u_4
inst✝³ : NormedCommRing A'
inst✝² : NormedAlgebra 𝕜 A'
inst✝¹ : DecidableEq ι
inst✝ : NormOneClass A'
u : Finset ι
f : ι → E → A'
N : ℕ∞ω
hf : ∀ i ∈ u, ContDiffOn 𝕜 N (f i) s
hs : UniqueDiffOn 𝕜 s
x : E
hx : x ∈ s
n : ℕ
hn : ↑n ≤ N
⊢ ‖iteratedFDerivWithin 𝕜 n (fun x ↦ ∏ j ∈ u, f j x) s x‖ ≤
    ∑ p ∈ u.sym n, ↑(↑p).countPerms * ∏ j ∈ u, ‖iteratedFDerivWithin 𝕜 (Multiset.count j ↑p) (f j) s x‖

Tactic:
induction u using Finset.induction generalizing n with

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

Goal state before:
pp: f : ℝ → ℝ
a b c : ℝ
hb : ContinuousAt f b
hc : ContinuousAt f c
hd₀ : DifferentiableOn ℝ f (Ioo a b)
hd₁ : DifferentiableOn ℝ f (Ioo b c)
h₀ : ∀ x ∈ Ioo a b, 0 ≤ deriv f x
h₁ : ∀ x ∈ Ioo b c, deriv f x ≤ 0
⊢ IsMaxOn f (Ioc a c) b

Tactic:
by
  refine isMaxOn_Ioc_of_mono_anti ?_ ?_
  · apply monotoneOn_of_deriv_nonneg (convex_Ioc a b) (continuousOn_Ioc hb hd₀) <;> simp_all
  · apply antitoneOn_of_deriv_nonpos (convex_Icc b c) (continuousOn_Icc hb hc hd₁) <;> simp_all

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

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁴ : NontriviallyNormedField 𝕜
E : Type u_2
F : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace 𝕜 F
s : Set E
f : E → F
x : E
hs : UniqueDiffOn 𝕜 s
hx : x ∈ s
h : IsSymmSndFDerivWithinAt 𝕜 f univ x
hf : ContDiffWithinAt 𝕜 2 f univ x
⊢ IsSymmSndFDerivWithinAt 𝕜 f s x

Tactic:
exact h.mono_of_mem_nhdsWithin univ_mem hf hs uniqueDiffOn_univ hx

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

Goal state before:
pp: case hf.hf.hf
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 := ⋯
g' : ℝ → F := ⋯
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
t : ℝ
ht : t ∈ Icc 0 1
⊢ HasDerivWithinAt (fun t ↦ f (x + h • v + (t * h) • w)) ((f' (x + h • v + (t * h) • w)) (h • w)) (Icc 0 1) t

Tactic:
refine (hf _ ?_).comp_hasDerivWithinAt _ ?_
      · exact xt_mem t ht
      apply_rules [HasDerivAt.hasDerivWithinAt, HasDerivAt.const_add, HasDerivAt.smul_const,
        hasDerivAt_mul_const]

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

Goal state before:
pp: 𝕜 : Type u_1
inst✝² : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
W : E → E
s : Set E
⊢ lieBracketWithin 𝕜 0 W s = 0

Tactic:
by ext; simp [lieBracketWithin]

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

Goal state before:
pp: 𝕜 : Type u_1
inst✝² : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
W : E → E
s : Set E
⊢ lieBracketWithin 𝕜 W 0 s = 0

Tactic:
by ext; simp [lieBracketWithin]

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

Goal state before:
pp: case neg
𝕜 : Type u_1
inst✝ : NontriviallyNormedField 𝕜
n : ℕ∞ω
m : ℕ
hm : (if IsRCLikeNormedField 𝕜 then ↑m else ω) ≤ n
h : ¬IsRCLikeNormedField 𝕜
⊢ ∃ n', ω ≤ n' ∧ n' ≤ n ∧ n' ≠ ∞

Tactic:
simp only [h, ↓reduceIte] at hm
    refine ⟨ω, le_rfl, by simp [hm], by simp⟩

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

Goal state before:
pp: case neg
E : Type u_1
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x : E
t : ℝ
h✝ : Nontrivial E
hd : ¬DifferentiableAt ℝ (fun x ↦ ‖x‖) x
⊢ ¬DifferentiableAt ℝ (fun x ↦ ‖x‖) (t • x)

Tactic:
· exact mt DifferentiableAt.differentiableAt_norm_of_smul hd

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
⊢ ContDiffAt 𝕜 n (cdf.implicitFunction pn if₂) u.1

Tactic:
by
  rw [ContDiffAt.implicitFunction_def, HasStrictFDerivAt.implicitFunctionOfProdDomain_def]
  set φ := (cdf.hasStrictFDerivAt pn).implicitFunctionDataOfProdDomain if₂
  have : ContDiffAt 𝕜 n φ.implicitFunction.uncurry (f u, u.1) := by
    simpa [φ] using φ.contDiffAt_implicitFunction
      (by simpa [φ] using cdf) (by simpa [φ] using contDiffAt_fst) pn
  fun_prop

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
⊢ (fderiv 𝕜 φ.prodFun φ.pt).IsInvertible

Tactic:
by
  rw [φ.hasStrictFDerivAt.hasFDerivAt.fderiv]
  exact ContinuousLinearMap.isInvertible_equiv

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
x : G
⊢ φ.leftDeriv ((fderiv 𝕜 (φ.implicitFunction (φ.leftFun φ.pt)) (φ.rightFun φ.pt)) x) = 0

Tactic:
exact φ.fderiv_implicitFunction_apply_eq_iff.mp rfl |>.left

Goal state after:
Module: Mathlib.Analysis.Calculus.IteratedDeriv.FaaDiBruno

Goal state before:
pp: 𝕜 : Type u_1
inst✝ : NontriviallyNormedField 𝕜
g f : 𝕜 → 𝕜
s t : Set 𝕜
x : 𝕜
hg : ContDiffWithinAt 𝕜 2 g t (f x)
hf : ContDiffWithinAt 𝕜 2 f s x
ht : UniqueDiffOn 𝕜 t
hs : UniqueDiffOn 𝕜 s
hx : x ∈ s
hst : MapsTo f s t
⊢ iteratedDerivWithin 2 (g ∘ f) s x =
    iteratedDerivWithin 2 g t (f x) * derivWithin f s x ^ 2 + derivWithin g t (f x) * iteratedDerivWithin 2 f s x

Tactic:
iteratedDerivWithin_scomp_two hg hf ht hs hx hst

Goal state after:
𝕜 : Type u_1
inst✝ : NontriviallyNormedField 𝕜
g f : 𝕜 → 𝕜
s t : Set 𝕜
x : 𝕜
hg : ContDiffWithinAt 𝕜 2 g t (f x)
hf : ContDiffWithinAt 𝕜 2 f s x
ht : UniqueDiffOn 𝕜 t
hs : UniqueDiffOn 𝕜 s
hx : x ∈ s
hst : MapsTo f s t
⊢ derivWithin f s x ^ 2 • iteratedDerivWithin 2 g t (f x) + iteratedDerivWithin 2 f s x • derivWithin g t (f x) =
    iteratedDerivWithin 2 g t (f x) * derivWithin f s x ^ 2 + derivWithin g t (f x) * iteratedDerivWithin 2 f s x
Module: Mathlib.Analysis.Calculus.LHopital

Goal state before:
pp: a b : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hab : a < b
hff' : ∀ x ∈ Ioo a b, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Ioo a b, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Ioo a b, g' x ≠ 0
hfb : Tendsto f (𝓝[<] b) (𝓝 0)
hgb : Tendsto g (𝓝[<] b) (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) (𝓝[<] b) l
hdnf : ∀ x ∈ Ioo (-b) (-a), HasDerivAt (f ∘ Neg.neg) (f' (-x) * -1) x
hdng : ∀ x ∈ Ioo (-b) (-a), HasDerivAt (g ∘ Neg.neg) (g' (-x) * -1) x
this✝ : Tendsto (fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) (𝓝[>] (-b)) l
this : Tendsto ((fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) ∘ Neg.neg) (𝓝[<] b) l
⊢ Tendsto (fun x ↦ f x / g x) (𝓝[<] b) l

Tactic:
unfold Function.comp at this

Goal state after:
a b : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hab : a < b
hff' : ∀ x ∈ Ioo a b, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Ioo a b, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Ioo a b, g' x ≠ 0
hfb : Tendsto f (𝓝[<] b) (𝓝 0)
hgb : Tendsto g (𝓝[<] b) (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) (𝓝[<] b) l
hdnf : ∀ x ∈ Ioo (-b) (-a), HasDerivAt (f ∘ Neg.neg) (f' (-x) * -1) x
hdng : ∀ x ∈ Ioo (-b) (-a), HasDerivAt (g ∘ Neg.neg) (g' (-x) * -1) x
this✝ : Tendsto (fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) (𝓝[>] (-b)) l
this : Tendsto (fun x ↦ (fun x ↦ f (-x) / g (-x)) (-x)) (𝓝[<] b) l
⊢ Tendsto (fun x ↦ f x / g x) (𝓝[<] b) l
Module: Mathlib.Analysis.Calculus.LHopital

Goal state before:
pp: a : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hff' : ∀ x ∈ Ioi a, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Ioi a, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Ioi a, g' x ≠ 0
hftop : Tendsto f atTop (𝓝 0)
hgtop : Tendsto g atTop (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) atTop l
a' : ℝ
haa' : a < a'
ha' : 0 < a'
fact1 : ∀ x ∈ Ioo 0 a'⁻¹, x ≠ 0
fact2 : ∀ x ∈ Ioo 0 a'⁻¹, a < x⁻¹
hdnf : ∀ x ∈ Ioo 0 a'⁻¹, HasDerivAt (f ∘ Inv.inv) (f' x⁻¹ * -(x ^ 2)⁻¹) x
hdng : ∀ x ∈ Ioo 0 a'⁻¹, HasDerivAt (g ∘ Inv.inv) (g' x⁻¹ * -(x ^ 2)⁻¹) x
this✝ : Tendsto (fun x ↦ (f ∘ Inv.inv) x / (g ∘ Inv.inv) x) (𝓝[>] 0) l
this : Tendsto ((fun x ↦ (f ∘ Inv.inv) x / (g ∘ Inv.inv) x) ∘ fun r ↦ r⁻¹) atTop l
⊢ Tendsto (fun x ↦ f x / g x) atTop l

Tactic:
unfold Function.comp at this

Goal state after:
a : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hff' : ∀ x ∈ Ioi a, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Ioi a, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Ioi a, g' x ≠ 0
hftop : Tendsto f atTop (𝓝 0)
hgtop : Tendsto g atTop (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) atTop l
a' : ℝ
haa' : a < a'
ha' : 0 < a'
fact1 : ∀ x ∈ Ioo 0 a'⁻¹, x ≠ 0
fact2 : ∀ x ∈ Ioo 0 a'⁻¹, a < x⁻¹
hdnf : ∀ x ∈ Ioo 0 a'⁻¹, HasDerivAt (f ∘ Inv.inv) (f' x⁻¹ * -(x ^ 2)⁻¹) x
hdng : ∀ x ∈ Ioo 0 a'⁻¹, HasDerivAt (g ∘ Inv.inv) (g' x⁻¹ * -(x ^ 2)⁻¹) x
this✝ : Tendsto (fun x ↦ (f ∘ Inv.inv) x / (g ∘ Inv.inv) x) (𝓝[>] 0) l
this : Tendsto (fun x ↦ (fun x ↦ f x⁻¹ / g x⁻¹) ((fun r ↦ r⁻¹) x)) atTop l
⊢ Tendsto (fun x ↦ f x / g x) atTop l
Module: Mathlib.Analysis.Calculus.LHopital

Goal state before:
pp: a : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hff' : ∀ x ∈ Iio a, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Iio a, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Iio a, g' x ≠ 0
hfbot : Tendsto f atBot (𝓝 0)
hgbot : Tendsto g atBot (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) atBot l
hdnf : ∀ x ∈ Ioi (-a), HasDerivAt (f ∘ Neg.neg) (f' (-x) * -1) x
hdng : ∀ x ∈ Ioi (-a), HasDerivAt (g ∘ Neg.neg) (g' (-x) * -1) x
this✝ : Tendsto (fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) atTop l
this : Tendsto ((fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) ∘ Neg.neg) atBot l
⊢ Tendsto (fun x ↦ f x / g x) atBot l

Tactic:
unfold Function.comp at this

Goal state after:
a : ℝ
l : Filter ℝ
f f' g g' : ℝ → ℝ
hff' : ∀ x ∈ Iio a, HasDerivAt f (f' x) x
hgg' : ∀ x ∈ Iio a, HasDerivAt g (g' x) x
hg' : ∀ x ∈ Iio a, g' x ≠ 0
hfbot : Tendsto f atBot (𝓝 0)
hgbot : Tendsto g atBot (𝓝 0)
hdiv : Tendsto (fun x ↦ f' x / g' x) atBot l
hdnf : ∀ x ∈ Ioi (-a), HasDerivAt (f ∘ Neg.neg) (f' (-x) * -1) x
hdng : ∀ x ∈ Ioi (-a), HasDerivAt (g ∘ Neg.neg) (g' (-x) * -1) x
this✝ : Tendsto (fun x ↦ (f ∘ Neg.neg) x / (g ∘ Neg.neg) x) atTop l
this : Tendsto (fun x ↦ (fun x ↦ f (-x) / g (-x)) (-x)) atBot l
⊢ Tendsto (fun x ↦ f x / g x) atBot l
Module: Mathlib.MeasureTheory.Function.Jacobian

Goal state before:
pp: E : Type u_1
F✝ : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : FiniteDimensional ℝ E
inst✝² : NormedAddCommGroup F✝
inst✝¹ : NormedSpace ℝ F✝
inst✝ : SecondCountableTopology F✝
f : E → F✝
s : Set E
f' : E → E →L[ℝ] F✝
hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
r : (E →L[ℝ] F✝) → ℝ≥0
rpos : ∀ (A : E →L[ℝ] F✝), r A ≠ 0
hs : s.Nonempty
T : Set ↑s
T_count : T.Countable
hT : ⋃ x ∈ T, ball (f' ↑x) ↑(r (f' ↑x)) = ⋃ x, ball (f' ↑x) ↑(r (f' ↑x))
u : ℕ → ℝ
left✝ : StrictAnti u
u_pos : ∀ (n : ℕ), 0 < u n
u_lim : Tendsto u atTop (𝓝 0)
M : ℕ → ↑T → Set E := ⋯
s_subset : ∀ x ∈ s, ∃ n z, x ∈ M n z
closure_M_subset : ∀ (n : ℕ) (z : ↑T), s ∩ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (M n z) ⊆ M n z
d : ℕ → E
hd : DenseRange d
K : ℕ → ↑T → ℕ → Set E := ⋯
K_approx : ∀ (n : ℕ) (z : ↑T) (p : ℕ), ApproximatesLinearOn f (f' ↑↑z) (s ∩ K n z p) (r (f' ↑↑z))
K_closed : ∀ (n : ℕ) (z : ↑T) (p : ℕ), IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (K n z p)
F : ℕ → ℕ × ↑T × ℕ
hF : Function.Surjective F
x : E
xs : x ∈ s
n : ℕ
z : ↑T
hnz : x ∈ M n z
p : ℕ
hp : x ∈ closedBall (d p) (u n / 3)
q : ℕ
hq : F q = (n, z, p)
⊢ x ∈ K (F q).1 (F q).2.1 (F q).2.2

Tactic:
simp -zeta only [K, hq, mem_inter_iff, hp, and_true]

Goal state after:
E : Type u_1
F✝ : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : FiniteDimensional ℝ E
inst✝² : NormedAddCommGroup F✝
inst✝¹ : NormedSpace ℝ F✝
inst✝ : SecondCountableTopology F✝
f : E → F✝
s : Set E
f' : E → E →L[ℝ] F✝
hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
r : (E →L[ℝ] F✝) → ℝ≥0
rpos : ∀ (A : E →L[ℝ] F✝), r A ≠ 0
hs : s.Nonempty
T : Set ↑s
T_count : T.Countable
hT : ⋃ x ∈ T, ball (f' ↑x) ↑(r (f' ↑x)) = ⋃ x, ball (f' ↑x) ↑(r (f' ↑x))
u : ℕ → ℝ
left✝ : StrictAnti u
u_pos : ∀ (n : ℕ), 0 < u n
u_lim : Tendsto u atTop (𝓝 0)
M : ℕ → ↑T → Set E :=
  fun n z ↦ {x | x ∈ s ∧ ∀ y ∈ s ∩ ball x (u n), ‖f y - f x - (f' ↑↑z) (y - x)‖ ≤ ↑(r (f' ↑↑z)) * ‖y - x‖}
s_subset : ∀ x ∈ s, ∃ n z, x ∈ M n z
closure_M_subset : ∀ (n : ℕ) (z : ↑T), s ∩ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (M n z) ⊆ M n z
d : ℕ → E
hd : DenseRange d
K : ℕ → ↑T → ℕ → Set E :=
  fun n z p ↦ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (M n z) ∩ closedBall (d p) (u n / 3)
K_approx : ∀ (n : ℕ) (z : ↑T) (p : ℕ), ApproximatesLinearOn f (f' ↑↑z) (s ∩ K n z p) (r (f' ↑↑z))
K_closed : ∀ (n : ℕ) (z : ↑T) (p : ℕ), IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (K n z p)
F : ℕ → ℕ × ↑T × ℕ
hF : Function.Surjective F
x : E
xs : x ∈ s
n : ℕ
z : ↑T
hnz : x ∈ M n z
p : ℕ
hp : x ∈ closedBall (d p) (u n / 3)
q : ℕ
hq : F q = (n, z, p)
⊢ x ∈ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (M n z)
Module: Mathlib.MeasureTheory.Function.Jacobian

Goal state before:
pp: case refine_2
E : Type u_1
F : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : FiniteDimensional ℝ E
inst✝⁴ : NormedAddCommGroup F
inst✝³ : NormedSpace ℝ F
inst✝² : MeasurableSpace E
inst✝¹ : BorelSpace E
inst✝ : SecondCountableTopology F
f : E → F
s : Set E
f' : E → E →L[ℝ] F
hf' : ∀ x ∈ s, HasFDerivWithinAt f (f' x) s x
r : (E →L[ℝ] F) → ℝ≥0
rpos : ∀ (A : E →L[ℝ] F), r A ≠ 0
t : ℕ → Set E
A : ℕ → E →L[ℝ] F
t_closed : ∀ (n : ℕ), IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (t n)
st : s ⊆ ⋃ n, t n
t_approx : ∀ (n : ℕ), ApproximatesLinearOn f (A n) (s ∩ t n) (r (A n))
ht : s.Nonempty → ∀ (n : ℕ), ∃ y ∈ s, A n = f' y
⊢ ∀ (n : ℕ), ApproximatesLinearOn f (A n) (s ∩ disjointed t n) (r (A n))

Tactic:
· intro n; exact (t_approx n).mono_set (inter_subset_inter_right _ (disjointed_subset _ _))

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

Goal state before:
pp: l : Filter ℝ
f g : ℝ → ℝ
hdf : ∀ᶠ (x : ℝ) in atTop, DifferentiableAt ℝ f x
hg' : ∀ᶠ (x : ℝ) in atTop, deriv g x ≠ 0
hftop : Tendsto f atTop (𝓝 0)
hgtop : Tendsto g atTop (𝓝 0)
hdiv : Tendsto (fun x ↦ deriv f x / deriv g x) atTop l
⊢ Tendsto (fun x ↦ f x / g x) atTop l

Tactic:
have hdg : ∀ᶠ x in atTop, DifferentiableAt ℝ g x := hg'.mp
    (Eventually.of_forall fun _ hg' =>
      by_contradiction fun h => hg' (deriv_zero_of_not_differentiableAt h))

Goal state after:
l : Filter ℝ
f g : ℝ → ℝ
hdf : ∀ᶠ (x : ℝ) in atTop, DifferentiableAt ℝ f x
hg' : ∀ᶠ (x : ℝ) in atTop, deriv g x ≠ 0
hftop : Tendsto f atTop (𝓝 0)
hgtop : Tendsto g atTop (𝓝 0)
hdiv : Tendsto (fun x ↦ deriv f x / deriv g x) atTop l
hdg : ∀ᶠ (x : ℝ) in atTop, DifferentiableAt ℝ g x
⊢ Tendsto (fun x ↦ f x / g x) atTop l