mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Geometry.Manifold.PartitionOfUnity

Goal state before:
pp: E : Type uE
inst✝¹⁶ : NormedAddCommGroup E
inst✝¹⁵ : NormedSpace ℝ E
H : Type uH
inst✝¹⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type uM
inst✝¹³ : TopologicalSpace M
inst✝¹² : ChartedSpace H M
inst✝¹¹ : FiniteDimensional ℝ E
inst✝¹⁰ : IsManifold I ∞ M
inst✝⁹ : SigmaCompactSpace M
inst✝⁸ : T2Space M
n : ℕ∞
F_fiber : Type u_1
inst✝⁷ : NormedAddCommGroup F_fiber
inst✝⁶ : NormedSpace ℝ F_fiber
V : M → Type u_2
inst✝⁵ : (x : M) → AddCommGroup (V x)
inst✝⁴ : (x : M) → TopologicalSpace (V x)
inst✝³ : (x : M) → Module ℝ (V x)
inst✝² : TopologicalSpace (TotalSpace F_fiber V)
inst✝¹ : FiberBundle F_fiber V
inst✝ : VectorBundle ℝ F_fiber V
t : (x : M) → Set (V x)
ht_conv : ∀ (x : M), Convex ℝ (t x)
W : M → Set M
h_nhds : ∀ (x₀ : M), W x₀ ∈ 𝓝 x₀
s_loc : M → (x : M) → V x
s_smooth : ∀ (x₀ : M), ContMDiffOn I (I.prod 𝓘(ℝ, F_fiber)) (↑n) (fun x ↦ ⟨x, s_loc x₀ x⟩) (W x₀)
h_mem_t : ∀ (x₀ y : M), y ∈ W x₀ → s_loc x₀ y ∈ t y
U : M → Set M := fun x ↦ interior (W x)
⊢ univ ⊆ ⋃ x, U x

Tactic:
intro x_pt

Goal state after:
E : Type uE
inst✝¹⁶ : NormedAddCommGroup E
inst✝¹⁵ : NormedSpace ℝ E
H : Type uH
inst✝¹⁴ : TopologicalSpace H
I : ModelWithCorners ℝ E H
M : Type uM
inst✝¹³ : TopologicalSpace M
inst✝¹² : ChartedSpace H M
inst✝¹¹ : FiniteDimensional ℝ E
inst✝¹⁰ : IsManifold I ∞ M
inst✝⁹ : SigmaCompactSpace M
inst✝⁸ : T2Space M
n : ℕ∞
F_fiber : Type u_1
inst✝⁷ : NormedAddCommGroup F_fiber
inst✝⁶ : NormedSpace ℝ F_fiber
V : M → Type u_2
inst✝⁵ : (x : M) → AddCommGroup (V x)
inst✝⁴ : (x : M) → TopologicalSpace (V x)
inst✝³ : (x : M) → Module ℝ (V x)
inst✝² : TopologicalSpace (TotalSpace F_fiber V)
inst✝¹ : FiberBundle F_fiber V
inst✝ : VectorBundle ℝ F_fiber V
t : (x : M) → Set (V x)
ht_conv : ∀ (x : M), Convex ℝ (t x)
W : M → Set M
h_nhds : ∀ (x₀ : M), W x₀ ∈ 𝓝 x₀
s_loc : M → (x : M) → V x
s_smooth : ∀ (x₀ : M), ContMDiffOn I (I.prod 𝓘(ℝ, F_fiber)) (↑n) (fun x ↦ ⟨x, s_loc x₀ x⟩) (W x₀)
h_mem_t : ∀ (x₀ y : M), y ∈ W x₀ → s_loc x₀ y ∈ t y
U : M → Set M := fun x ↦ interior (W x)
x_pt : M
⊢ x_pt ∈ univ → x_pt ∈ ⋃ x, U x
Module: Mathlib.MeasureTheory.Function.AEEqOfIntegral

Goal state before:
pp: case h
α : Type u_1
E : Type u_2
𝕜 : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
t : Set E
f : α → E
hf : ∀ (c : StrongDual 𝕜 E), (fun x ↦ c (f x)) =ᵐ[μ] 0
h't : ∀ᵐ (x : α) ∂μ, f x ∈ t
d : Set E
d_count : d.Countable
hd : t ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] d
this : Encodable ↑d
s : ↑d → StrongDual 𝕜 E
hs : ∀ (x : ↑d), ‖s x‖ ≤ 1 ∧ (s x) ↑x = ↑‖↑x‖
a : E
hat : a ∈ t
ha : a ≠ 0
a_pos : 0 < ‖a‖
a_mem : a ∈ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] d
x : ↑d
hx : dist a ↑x < ‖a‖ / 2
I : ‖a‖ / 2 < ‖↑x‖
⊢ (s x) a ≠ 0

Tactic:
intro h

Goal state after:
case h
α : Type u_1
E : Type u_2
𝕜 : Type u_3
m : MeasurableSpace α
μ : Measure α
inst✝² : RCLike 𝕜
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace 𝕜 E
t : Set E
f : α → E
hf : ∀ (c : StrongDual 𝕜 E), (fun x ↦ c (f x)) =ᵐ[μ] 0
h't : ∀ᵐ (x : α) ∂μ, f x ∈ t
d : Set E
d_count : d.Countable
hd : t ⊆ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] d
this : Encodable ↑d
s : ↑d → StrongDual 𝕜 E
hs : ∀ (x : ↑d), ‖s x‖ ≤ 1 ∧ (s x) ↑x = ↑‖↑x‖
a : E
hat : a ∈ t
ha : a ≠ 0
a_pos : 0 < ‖a‖
a_mem : a ∈ closure[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] d
x : ↑d
hx : dist a ↑x < ‖a‖ / 2
I : ‖a‖ / 2 < ‖↑x‖
h : (s x) a = 0
⊢ False
Module: Mathlib.MeasureTheory.Function.AEEqOfIntegral

Goal state before:
pp: α : Type u_1
m0 : MeasurableSpace α
μ : Measure α
f : α → ℝ
hf : Integrable f μ
hf_zero : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → 0 ≤ ∫ (x : α) in s, f x ∂μ
b : ℝ
hb_neg : b < 0
s : Set α := {x | f x ≤ b}
⊢ μ {x | f x ≤ b} = 0

Tactic:
have hs : NullMeasurableSet s μ := nullMeasurableSet_le hf.1.aemeasurable aemeasurable_const

Goal state after:
α : Type u_1
m0 : MeasurableSpace α
μ : Measure α
f : α → ℝ
hf : Integrable f μ
hf_zero : ∀ (s : Set α), MeasurableSet s → μ s < ∞ → 0 ≤ ∫ (x : α) in s, f x ∂μ
b : ℝ
hb_neg : b < 0
s : Set α := {x | f x ≤ b}
hs : NullMeasurableSet s μ
⊢ μ {x | f x ≤ b} = 0
Module: Mathlib.Analysis.Calculus.Rademacher

Goal state before:
pp: case h_bound
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
C : ℝ≥0
f g : E → ℝ
μ : Measure E
inst✝¹ : FiniteDimensional ℝ E
inst✝ : μ.IsAddHaarMeasure
hf : LipschitzWith C f
hg : Integrable g μ
v : E
⊢ ∀ᶠ (n : ℝ) in 𝓝[>] 0, ∀ᵐ (a : E) ∂μ, ‖n⁻¹ • (f (a + n • v) - f a) * g a‖ ≤ ↑C * ‖v‖ * ‖g a‖

pp: case bound_integrable
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
C : ℝ≥0
f g : E → ℝ
μ : Measure E
inst✝¹ : FiniteDimensional ℝ E
inst✝ : μ.IsAddHaarMeasure
hf : LipschitzWith C f
hg : Integrable g μ
v : E
⊢ Integrable (fun x ↦ ↑C * ‖v‖ * ‖g x‖) μ

pp: case h_lim
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
C : ℝ≥0
f g : E → ℝ
μ : Measure E
inst✝¹ : FiniteDimensional ℝ E
inst✝ : μ.IsAddHaarMeasure
hf : LipschitzWith C f
hg : Integrable g μ
v : E
⊢ ∀ᵐ (a : E) ∂μ, Tendsto (fun n ↦ n⁻¹ • (f (a + n • v) - f a) * g a) (𝓝[>] 0) (𝓝 (lineDeriv ℝ f a v * g a))

Tactic:
· filter_upwards [self_mem_nhdsWithin] with t (ht : 0 < t)
    filter_upwards with x
    calc ‖t⁻¹ • (f (x + t • v) - f x) * g x‖
      = (t⁻¹ * ‖f (x + t • v) - f x‖) * ‖g x‖ := by simp [norm_mul, ht.le]
    _ ≤ (t⁻¹ * (C * ‖(x + t • v) - x‖)) * ‖g x‖ := by
      gcongr; exact LipschitzWith.norm_sub_le hf (x + t • v) x
    _ = (C * ‖v‖) * ‖g x‖ := by simp [field, norm_smul, abs_of_nonneg ht.le]

Goal state after:
case bound_integrable
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
C : ℝ≥0
f g : E → ℝ
μ : Measure E
inst✝¹ : FiniteDimensional ℝ E
inst✝ : μ.IsAddHaarMeasure
hf : LipschitzWith C f
hg : Integrable g μ
v : E
⊢ Integrable (fun x ↦ ↑C * ‖v‖ * ‖g x‖) μ

case h_lim
E : Type u_1
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace ℝ E
inst✝³ : MeasurableSpace E
inst✝² : BorelSpace E
C : ℝ≥0
f g : E → ℝ
μ : Measure E
inst✝¹ : FiniteDimensional ℝ E
inst✝ : μ.IsAddHaarMeasure
hf : LipschitzWith C f
hg : Integrable g μ
v : E
⊢ ∀ᵐ (a : E) ∂μ, Tendsto (fun n ↦ n⁻¹ • (f (a + n • v) - f a) * g a) (𝓝[>] 0) (𝓝 (lineDeriv ℝ f a v * g a))
Module: Mathlib.Analysis.Calculus.TangentCone.Seq

Goal state before:
pp: case mp
R : Type u_1
E : Type u_2
inst✝³ : AddCommGroup E
inst✝² : SMul R E
inst✝¹ : TopologicalSpace E
inst✝ : FirstCountableTopology E
s : Set E
x y : E
⊢ y ∈ tangentConeAt R s x →
    ∃ c d, Tendsto d atTop (𝓝 0) ∧ (∀ᶠ (n : ℕ) in atTop, x + d n ∈ s) ∧ Tendsto (fun n ↦ c n • d n) atTop (𝓝 y)

Tactic:
intro h

Goal state after:
case mp
R : Type u_1
E : Type u_2
inst✝³ : AddCommGroup E
inst✝² : SMul R E
inst✝¹ : TopologicalSpace E
inst✝ : FirstCountableTopology E
s : Set E
x y : E
h : y ∈ tangentConeAt R s x
⊢ ∃ c d, Tendsto d atTop (𝓝 0) ∧ (∀ᶠ (n : ℕ) in atTop, x + d n ∈ s) ∧ Tendsto (fun n ↦ c n • d n) atTop (𝓝 y)
Module: Mathlib.MeasureTheory.Function.AEEqOfIntegral

Goal state before:
pp: E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : CompleteSpace E
β : Type u_3
inst✝⁴ : TopologicalSpace β
inst✝³ : MeasurableSpace β
inst✝² : BorelSpace β
inst✝¹ : SigmaCompactSpace β
inst✝ : R1Space β
μ : Measure β
f : β → E
hf : Integrable f μ
h'f : ∀ (s : Set β), IsCompact s → ∫ (x : β) in s, f x ∂μ = 0
s : Set β
hs : IsClosed[inst✝⁴] s
t : ℕ → Set β := fun n ↦ closure[inst✝⁴] (compactCovering β n) ∩ s
H : Tendsto (fun n ↦ ∫ (x : β) in t n, f x ∂μ) atTop (𝓝 (∫ (x : β) in s, f x ∂μ))
A : ∀ (n : ℕ), ∫ (x : β) in t n, f x ∂μ = 0
⊢ ∫ (x : β) in s, f x ∂μ = 0

Tactic:
simp_rw [A, tendsto_const_nhds_iff] at H

Goal state after:
E : Type u_2
inst✝⁷ : NormedAddCommGroup E
inst✝⁶ : NormedSpace ℝ E
inst✝⁵ : CompleteSpace E
β : Type u_3
inst✝⁴ : TopologicalSpace β
inst✝³ : MeasurableSpace β
inst✝² : BorelSpace β
inst✝¹ : SigmaCompactSpace β
inst✝ : R1Space β
μ : Measure β
f : β → E
hf : Integrable f μ
h'f : ∀ (s : Set β), IsCompact s → ∫ (x : β) in s, f x ∂μ = 0
s : Set β
hs : IsClosed[inst✝⁴] s
t : ℕ → Set β := fun n ↦ closure[inst✝⁴] (compactCovering β n) ∩ s
A : ∀ (n : ℕ), ∫ (x : β) in t n, f x ∂μ = 0
H : 0 = ∫ (x : β) in s, f x ∂μ
⊢ ∫ (x : β) in s, f x ∂μ = 0
Module: Mathlib.Order.SuccPred.IntervalSucc

Goal state before:
pp: case inr.refine_2
α : Type u_1
β : Type u_2
inst✝³ : LinearOrder α
inst✝² : SuccOrder α
inst✝¹ : IsSuccArchimedean α
inst✝ : LinearOrder β
f : α → β
hf : Monotone f
m n : α
hmn : m ≤ n
k : α
hmk : m ≤ k
ihk : ⋃ i ∈ Ico m k, Ioc (f i) (f (succ i)) = Ioc (f m) (f k)
⊢ ⋃ i ∈ Ico m (succ k), Ioc (f i) (f (succ i)) = Ioc (f m) (f k) ∪ Ioc (f k) (f (succ k))

Tactic:
union_comm,

Goal state after:
case inr.refine_2
α : Type u_1
β : Type u_2
inst✝³ : LinearOrder α
inst✝² : SuccOrder α
inst✝¹ : IsSuccArchimedean α
inst✝ : LinearOrder β
f : α → β
hf : Monotone f
m n : α
hmn : m ≤ n
k : α
hmk : m ≤ k
ihk : ⋃ i ∈ Ico m k, Ioc (f i) (f (succ i)) = Ioc (f m) (f k)
⊢ ⋃ i ∈ Ico m (succ k), Ioc (f i) (f (succ i)) = Ioc (f k) (f (succ k)) ∪ Ioc (f m) (f k)
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Slope

Goal state before:
pp: f : ℝ → ℝ
a b c : ℝ
hf : MonotoneOn f (uIcc a (b + c))
hab : a ≤ b
hc✝ : 0 ≤ c
hc : 0 < c
hf' : IntervalIntegrable f volume a (b + c)
⊢ ∀ x ∈ Icc b (b + c), f x ≤ f (b + c)

Tactic:
intros; apply hf <;> grind [uIcc]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.Slope

Goal state before:
pp: f : ℝ → ℝ
a b c : ℝ
hf : MonotoneOn f (uIcc a (b + c))
hab : a ≤ b
hc✝ : 0 ≤ c
hc : 0 < c
hf' : IntervalIntegrable f volume a (b + c)
fU : ∫ (x : ℝ) in b..b + c, f x ≤ c * f (b + c)
⊢ ∀ x ∈ Icc a (a + c), f a ≤ f x

Tactic:
intros; apply hf <;> grind [uIcc]

Goal state after:
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.LebesgueDifferentiationThm

Goal state before:
pp: E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
f : ℝ → E
hf : LocallyIntegrable f volume
hg : ∀ (x y : ℝ), IntervalIntegrable f volume x y
LDT : ∀ᵐ (x : ℝ), Tendsto (fun a ↦ ⨍ (y : ℝ) in a, f y) ((vitaliFamily volume 1).filterAt x) (𝓝 (f x))
h : ∀ {a b : ℝ}, ∫ (t : ℝ) in Ioc a b, f t = ∫ (t : ℝ) in Icc a b, f t
x : ℝ
hx : Tendsto (fun a ↦ ⨍ (y : ℝ) in a, f y) ((vitaliFamily volume 1).filterAt x) (𝓝 (f x))
c : ℝ
⊢ HasDerivAt (fun x ↦ ∫ (t : ℝ) in c..x, f t) (f x) x

Tactic:
rw [hasDerivAt_iff_tendsto_slope_left_right]

Goal state after:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : CompleteSpace E
f : ℝ → E
hf : LocallyIntegrable f volume
hg : ∀ (x y : ℝ), IntervalIntegrable f volume x y
LDT : ∀ᵐ (x : ℝ), Tendsto (fun a ↦ ⨍ (y : ℝ) in a, f y) ((vitaliFamily volume 1).filterAt x) (𝓝 (f x))
h : ∀ {a b : ℝ}, ∫ (t : ℝ) in Ioc a b, f t = ∫ (t : ℝ) in Icc a b, f t
x : ℝ
hx : Tendsto (fun a ↦ ⨍ (y : ℝ) in a, f y) ((vitaliFamily volume 1).filterAt x) (𝓝 (f x))
c : ℝ
⊢ Tendsto (slope (fun x ↦ ∫ (t : ℝ) in c..x, f t) x) (𝓝[<] x) (𝓝 (f x)) ∧
    Tendsto (slope (fun x ↦ ∫ (t : ℝ) in c..x, f t) x) (𝓝[>] x) (𝓝 (f x))
Module: Mathlib.MeasureTheory.Function.AbsolutelyContinuous

Goal state before:
pp: F : Type u_2
inst✝³ : SeminormedAddCommGroup F
a b : ℝ
M : Type u_3
inst✝² : SeminormedRing M
inst✝¹ : Module M F
inst✝ : NormSMulClass M F
f : ℝ → M
g : ℝ → F
hf :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
hg :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (g (E.2 i).1) (g (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
C : ℝ
hC : ∀ x ∈ uIcc a b, ‖f x‖ ≤ C
D : ℝ
hD : ∀ x ∈ uIcc a b, ‖g x‖ ≤ D
⊢ AbsolutelyContinuousOnInterval (f • g) a b

Tactic:
apply squeeze_zero' ?_ ?_
    (by simpa using (hg.const_mul C).add (hf.const_mul D))

Goal state after:
F : Type u_2
inst✝³ : SeminormedAddCommGroup F
a b : ℝ
M : Type u_3
inst✝² : SeminormedRing M
inst✝¹ : Module M F
inst✝ : NormSMulClass M F
f : ℝ → M
g : ℝ → F
hf :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
hg :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (g (E.2 i).1) (g (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
C : ℝ
hC : ∀ x ∈ uIcc a b, ‖f x‖ ≤ C
D : ℝ
hD : ∀ x ∈ uIcc a b, ‖g x‖ ≤ D
⊢ ∀ᶠ (t : ℕ × (ℕ → ℝ × ℝ)) in totalLengthFilter ⊓ 𝓟 (disjWithin a b),
    0 ≤ ∑ i ∈ Finset.range t.1, dist ((f • g) (t.2 i).1) ((f • g) (t.2 i).2)

F : Type u_2
inst✝³ : SeminormedAddCommGroup F
a b : ℝ
M : Type u_3
inst✝² : SeminormedRing M
inst✝¹ : Module M F
inst✝ : NormSMulClass M F
f : ℝ → M
g : ℝ → F
hf :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
hg :
  Tendsto (fun E ↦ ∑ i ∈ Finset.range E.1, dist (g (E.2 i).1) (g (E.2 i).2)) (totalLengthFilter ⊓ 𝓟 (disjWithin a b))
    (𝓝 0)
C : ℝ
hC : ∀ x ∈ uIcc a b, ‖f x‖ ≤ C
D : ℝ
hD : ∀ x ∈ uIcc a b, ‖g x‖ ≤ D
⊢ ∀ᶠ (t : ℕ × (ℕ → ℝ × ℝ)) in totalLengthFilter ⊓ 𝓟 (disjWithin a b),
    ∑ i ∈ Finset.range t.1, dist ((f • g) (t.2 i).1) ((f • g) (t.2 i).2) ≤
      C * ∑ i ∈ Finset.range t.1, dist (g (t.2 i).1) (g (t.2 i).2) +
        D * ∑ i ∈ Finset.range t.1, dist (f (t.2 i).1) (f (t.2 i).2)
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.AbsolutelyContinuousFun

Goal state before:
pp: case hf
F : Type u_2
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f f' : ℝ → F
d b η : ℝ
hdb✝ : d ≤ b
hf : ∀ᵐ (x : ℝ), x ∈ Ioo d b → HasDerivAt f (f' x) x
hη : 0 < η
hdb : d < b
t : Set (ℝ × ℝ) := ⋯
s : Set ℝ := ⋯
⊢ ∀ x ∈ s, ∃ᶠ (ε : ℝ) in 𝓝[>] 0, ∃ a ∈ t, (Prod.snd - Prod.fst) a = ε ∧ a.1 = x

Tactic:
intro x hx
      apply Eventually.frequently
      have := hasDerivAt_iff_tendsto_slope.mp hx.right
      obtain ⟨δ, hδ₁, hδ₂⟩ := (Metric.tendsto_nhdsWithin_nhds).mp
        (hasDerivAt_iff_tendsto_slope.mp hx.right) η hη
      have evn_bound {α : ℝ} (hα : 0 < α) : ∀ᶠ (ε : ℝ) in 𝓝[>] 0, ε < α := by
        rw [eventually_nhdsWithin_iff, eventually_nhds_iff]
        exact ⟨Ioo (-α) α, by grind, isOpen_Ioo, by grind⟩
      have evn_pos : ∀ᶠ (ε : ℝ) in 𝓝[>] 0, 0 < ε :=
        eventually_mem_of_tendsto_nhdsWithin (fun _ a ↦ a)
      filter_upwards [evn_pos, evn_bound hη, evn_bound hδ₁,
                      evn_bound (α := (b - x) / 2) (by simp [hx.left.right])]
        with ε hε₁ hε₂ hε₃ hε₄
      refine ⟨(x, x + ε), ⟨⟨hx.1.1, by linarith, by linarith⟩, ?_⟩, by simp, rfl⟩
      exact hδ₂ (by grind) (by simp [abs_eq_self.mpr hε₁.le, hε₃])

Goal state after:
Module: Mathlib.MeasureTheory.Function.AbsolutelyContinuous

Goal state before:
pp: a b : ℝ
E : Type u_3
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
f : ℝ → E
hf : ContDiffOn ℝ 1 f (uIcc a b)
⊢ 1 ≠ 0

Tactic:
by decide

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

Goal state before:
pp: E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
inst✝⁴ : MeasurableSpace E
inst✝³ : BorelSpace E
C : ℝ≥0
μ : Measure E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : μ.IsAddHaarMeasure
ι : Type u_3
inst✝ : Fintype ι
f : E → ι → ℝ
s : Set E
hf : LipschitzOnWith C f s
A : ∀ (i : ι), LipschitzWith 1 fun x ↦ x i
this : ∀ (i : ι), ∀ᵐ (x : E) ∂μ, x ∈ s → DifferentiableWithinAt ℝ (fun x ↦ f x i) s x
⊢ ∀ᵐ (x : E) ∂μ, x ∈ s → DifferentiableWithinAt ℝ f s x

Tactic:
filter_upwards [ae_all_iff.2 this] with x hx xs

Goal state after:
E : Type u_1
inst✝⁶ : NormedAddCommGroup E
inst✝⁵ : NormedSpace ℝ E
inst✝⁴ : MeasurableSpace E
inst✝³ : BorelSpace E
C : ℝ≥0
μ : Measure E
inst✝² : FiniteDimensional ℝ E
inst✝¹ : μ.IsAddHaarMeasure
ι : Type u_3
inst✝ : Fintype ι
f : E → ι → ℝ
s : Set E
hf : LipschitzOnWith C f s
A : ∀ (i : ι), LipschitzWith 1 fun x ↦ x i
this : ∀ (i : ι), ∀ᵐ (x : E) ∂μ, x ∈ s → DifferentiableWithinAt ℝ (fun x ↦ f x i) s x
x : E
hx : ∀ (i : ι), x ∈ s → DifferentiableWithinAt ℝ (fun x ↦ f x i) s x
xs : x ∈ s
⊢ DifferentiableWithinAt ℝ f s x
Module: Mathlib.Analysis.Calculus.TaylorIntegral

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace ℝ E
inst✝¹ : NormedSpace ℝ F
f : E → F
x y : E
n : ℕ
inst✝ : CompleteSpace F
hf : ∀ t ∈ Set.uIcc 0 1, ContDiffAt ℝ (↑0 + 1) f (x + t • y)
h_eq : Set.EqOn (fun t ↦ (fderiv ℝ f (x + t • y)) y) (deriv fun s ↦ f (x + s • y)) (Set.uIcc 0 1)
hf' : ∀ t ∈ Set.uIcc 0 1, DifferentiableAt ℝ (fun s ↦ f (x + s • y)) t
h₁ : ContinuousOn (fderiv ℝ f) ((fun t ↦ x + t • y) '' Set.uIcc 0 1)
⊢ ContinuousOn (fun x_1 ↦ fderiv ℝ f (x + x_1 • y)) (Set.uIcc 0 1)

Tactic:
apply h₁.comp (t := (fun t ↦ x + t • y) '' (Set.uIcc (0 : ℝ) 1)) (by fun_prop)

Goal state after:
E : Type u_2
F : Type u_3
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedAddCommGroup F
inst✝² : NormedSpace ℝ E
inst✝¹ : NormedSpace ℝ F
f : E → F
x y : E
n : ℕ
inst✝ : CompleteSpace F
hf : ∀ t ∈ Set.uIcc 0 1, ContDiffAt ℝ (↑0 + 1) f (x + t • y)
h_eq : Set.EqOn (fun t ↦ (fderiv ℝ f (x + t • y)) y) (deriv fun s ↦ f (x + s • y)) (Set.uIcc 0 1)
hf' : ∀ t ∈ Set.uIcc 0 1, DifferentiableAt ℝ (fun s ↦ f (x + s • y)) t
h₁ : ContinuousOn (fderiv ℝ f) ((fun t ↦ x + t • y) '' Set.uIcc 0 1)
⊢ Set.MapsTo (fun x_1 ↦ x + x_1 • y) (Set.uIcc 0 1) ((fun t ↦ x + t • y) '' Set.uIcc 0 1)
Module: Mathlib.MeasureTheory.Integral.IntervalIntegral.AbsolutelyContinuousFun

Goal state before:
pp: F✝ : Type u_2
inst✝³ : NormedAddCommGroup F✝
inst✝² : NormedSpace ℝ F✝
F : Type u_2
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
a b : ℝ
hf : AbsolutelyContinuousOnInterval f a b
hf₀ : ∀ᵐ (x : ℝ), x ∈ Icc a b → HasDerivAt f 0 x
hab : a ≤ b
d : ℝ
hd : d ∈ Icc a b
this : ∀ r > 0, dist (f d) (f b) ≤ r
⊢ f d = f b

Tactic:
contrapose! this
    exact exists_between (dist_pos.mpr this)

Goal state after:
Module: Mathlib.Analysis.Complex.AbelLimit

Goal state before:
pp: s x y : ℝ
hx₀ : 0 < x
hx₁ : x < 1 / (1 + s ^ 2)
hy : |y| < s * x
⊢ √(1 - x) ≤ 1 - x / 2

Tactic:
simp_rw [sub_eq_add_neg, ← neg_div]

Goal state after:
s x y : ℝ
hx₀ : 0 < x
hx₁ : x < 1 / (1 + s ^ 2)
hy : |y| < s * x
⊢ √(1 + -x) ≤ 1 + -x / 2
Module: Mathlib.Analysis.Complex.AbelLimit

Goal state before:
pp: f : ℕ → ℂ
l : ℂ
h : Tendsto (fun n ↦ ∑ i ∈ range n, f i) atTop (𝓝 l)
z : ℂ
hz : ‖z‖ < 1
s : ℕ → ℂ := fun n ↦ ∑ i ∈ range n, f i
k :
  Tendsto (fun x ↦ (1 - z) * ∑ x_1 ∈ range x, (∑ i ∈ Ico (x_1 + 1) x, f i) * z ^ x_1) atTop
    (𝓝 (l - ∑' (i : ℕ), f i * z ^ i))
n : ℕ
| (1 - z) * ∑ x ∈ range n, (∑ i ∈ Ico (x + 1) n, f i) * z ^ x

Tactic:
rw [sum_congr (g := fun j ↦ (∑ k ∈ range n, f k - ∑ k ∈ range (j + 1), f k) * z ^ j)
      rfl (fun j hj ↦ by congr 1; exact sum_Ico_eq_sub _ (mem_range.mp hj))]

Goal state after:
f : ℕ → ℂ
l : ℂ
h : Tendsto (fun n ↦ ∑ i ∈ range n, f i) atTop (𝓝 l)
z : ℂ
hz : ‖z‖ < 1
s : ℕ → ℂ := fun n ↦ ∑ i ∈ range n, f i
k :
  Tendsto (fun x ↦ (1 - z) * ∑ x_1 ∈ range x, (∑ i ∈ Ico (x_1 + 1) x, f i) * z ^ x_1) atTop
    (𝓝 (l - ∑' (i : ℕ), f i * z ^ i))
n : ℕ
| (1 - z) * ∑ j ∈ range n, (∑ k ∈ range n, f k - ∑ k ∈ range (j + 1), f k) * z ^ j
Module: Mathlib.Analysis.Convex.StrictConvexSpace

Goal state before:
pp: E : Type u_2
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : StrictConvexSpace ℝ E
x y : E
h : ¬SameRay ℝ x y
⊢ ‖x‖ - ‖y‖ < ‖x - y‖

Tactic:
nth_rw 1 [← sub_add_cancel x y] at h ⊢
  exact sub_lt_iff_lt_add.2 (norm_add_lt_of_not_sameRay fun H' => h <| H'.add_left SameRay.rfl)

Goal state after:
Module: Mathlib.Analysis.Convex.SpecificFunctions.Deriv

Goal state before:
pp: m : ℤ
hm₀ : m ≠ 0
hm₁ : m ≠ 1
x : ℝ
hx : 0 < x
⊢ Even 2

Tactic:
by decide

Goal state after:
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Complex

Goal state before:
pp: x : ℂ
⊢ cos 0 = cos x ↔ ∃ k, ↑k * (2 * ↑π) = x

Tactic:
cos_eq_cos_iff

Goal state after:
x : ℂ
⊢ (∃ k, x = 2 * ↑k * ↑π + 0 ∨ x = 2 * ↑k * ↑π - 0) ↔ ∃ k, ↑k * (2 * ↑π) = x
Module: Mathlib.Analysis.Complex.AbsMax

Goal state before:
pp: E : Type u
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℂ E
F : Type v
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : Nontrivial E
f : E → F
U : Set E
hU : Bornology.IsBounded U
hd : DiffContOnCl ℂ f U
C : ℝ
hC : ∀ z ∈ frontier U, ‖f z‖ ≤ C
z : E
hz : z ∈ U ∪ frontier U
⊢ ‖f z‖ ≤ C

Tactic:
union_comm,

Goal state after:
E : Type u
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace ℂ E
F : Type v
inst✝² : NormedAddCommGroup F
inst✝¹ : NormedSpace ℂ F
inst✝ : Nontrivial E
f : E → F
U : Set E
hU : Bornology.IsBounded U
hd : DiffContOnCl ℂ f U
C : ℝ
hC : ∀ z ∈ frontier U, ‖f z‖ ≤ C
z : E
hz : z ∈ frontier U ∪ U
⊢ ‖f z‖ ≤ C
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Bounds

Goal state before:
pp: x : ℝ
hx : 0 ≤ x
⊢ sin x ≤ x

Tactic:
by
  obtain rfl | hx := hx.eq_or_lt
  · simp
  · exact (sin_lt hx).le

Goal state after:
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: 𝕜 : Type u_1
inst✝² : Field 𝕜
inst✝¹ : LinearOrder 𝕜
inst✝ : IsStrictOrderedRing 𝕜
s : Set 𝕜
f : 𝕜 → 𝕜
x : 𝕜
hfc : ConcaveOn 𝕜 s f
hx : x ∈ s
⊢ AntitoneOn (slope f x) (s \ {x})

Tactic:
by
  rw [← neg_neg f, slope_neg_fun]
  exact (ConvexOn.slope_mono hfc.neg hx).neg

Goal state after:
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: S : Set ℝ
f : ℝ → ℝ
x : ℝ
hfc : ConvexOn ℝ S f
hxs : x ∈ interior S
a b : ℝ
hxab : x ∈ Ioo a b
habs : Ioo a b ⊆ S
h : Ioo a x ⊆ {y | y ∈ S ∧ y < x}
⊢ Tendsto (slope f x) (𝓝[<] x) (𝓝 (sSup (slope f x '' {y | y ∈ S ∧ y < x})))

Tactic:
have h_Ioo : Tendsto (slope f x) (𝓝[<] x) (𝓝 (sSup (slope f x '' Ioo a x))) :=
    ((monotoneOn_slope_lt hfc (habs hxab)).mono h).tendsto_nhdsWithin_Ioo_left
      (by simpa using hxab.1) ((bddAbove_slope_gt_of_mem_interior hfc hxs).mono (image_mono h))

Goal state after:
S : Set ℝ
f : ℝ → ℝ
x : ℝ
hfc : ConvexOn ℝ S f
hxs : x ∈ interior S
a b : ℝ
hxab : x ∈ Ioo a b
habs : Ioo a b ⊆ S
h : Ioo a x ⊆ {y | y ∈ S ∧ y < x}
h_Ioo : Tendsto (slope f x) (𝓝[<] x) (𝓝 (sSup (slope f x '' Ioo a x)))
⊢ Tendsto (slope f x) (𝓝[<] x) (𝓝 (sSup (slope f x '' {y | y ∈ S ∧ y < x})))
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: S : Set ℝ
f : ℝ → ℝ
hfc : ConvexOn ℝ S f
⊢ MonotoneOn (fun x ↦ derivWithin f (Ioi x) x) (interior S)

Tactic:
by
  intro x hxs y hys hxy
  rcases eq_or_lt_of_le hxy with rfl | hxy; · rfl
  simp_rw [hfc.rightDeriv_eq_sInf_slope_of_mem_interior hxs,
    hfc.rightDeriv_eq_sInf_slope_of_mem_interior hys]
  refine csInf_le_of_le (b := slope f x y) (bddBelow_slope_lt_of_mem_interior hfc hxs)
    ⟨y, by simp only [mem_ofPred_eq, hxy, and_true]; exact interior_subset hys⟩
    (le_csInf ?_ ?_)
  · have hys' := hys
    rw [mem_interior_iff_mem_nhds, mem_nhds_iff_exists_Ioo_subset] at hys'
    obtain ⟨a, b, hxab, habs⟩ := hys'
    rw [image_nonempty]
    obtain ⟨z, hxz, hzb⟩ := exists_between hxab.2
    exact ⟨z, habs ⟨hxab.1.trans hxz, hzb⟩, hxz⟩
  · rintro _ ⟨z, ⟨hzs, hyz : y < z⟩, rfl⟩
    rw [slope_comm]
    exact slope_mono hfc (interior_subset hys) ⟨interior_subset hxs, hxy.ne⟩ ⟨hzs, hyz.ne'⟩
      (hxy.trans hyz).le

Goal state after:
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Arctan

Goal state before:
pp: x : ℝ
⊢ 0 ≤ sin (arctan x) ↔ 0 ≤ x

Tactic:
simpa using sin_arctan_strictMono.le_iff_le (a := 0)

Goal state after:
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Arctan

Goal state before:
pp: x : ℝ
⊢ sin (arctan x) ≤ 0 ↔ x ≤ 0

Tactic:
simpa using sin_arctan_strictMono.le_iff_le (b := 0)

Goal state after:
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Bounds

Goal state before:
pp: x : ℝ
hx1 : -(3 * π / 2) ≤ x
hx2 : x ≤ 3 * π / 2
⊢ cos x ≤ 1 / √(x ^ 2 + 1)

Tactic:
rcases eq_or_ne x 0 with (rfl | hx3)
  · simp
  · exact (cos_lt_one_div_sqrt_sq_add_one hx1 hx2 hx3).le

Goal state after: