mathlib-initiative/mathlib-tactics huggingface dataset:
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
⊢ ContinuousOn (fderiv ℝ f) ((fun t ↦ x + t • y) '' Set.uIcc 0 1)

Tactic:
intro z ⟨t, ht, hz⟩

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
z : E
t : ℝ
ht : t ∈ Set.uIcc 0 1
hz : (fun t ↦ x + t • y) t = z
⊢ ContinuousWithinAt (fderiv ℝ f) ((fun t ↦ x + t • y) '' Set.uIcc 0 1) z
Module: Mathlib.Analysis.Calculus.Taylor

Goal state before:
pp: case e'_2.x
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
⊢ ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t =
    ∫ (x_1 : ℝ) in x₀..x,
      -((deriv (fun x_2 ↦ (x - x_2) ^ (n + 1)) x_1 / ↑(n.succ * n !)) • iteratedDerivWithin (n + 1) f [[x₀, x]] x_1)

Tactic:
congr

Goal state after:
case e'_2.x.e_f
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
⊢ (fun t ↦ ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t) = fun x_1 ↦
    -((deriv (fun x_2 ↦ (x - x_2) ^ (n + 1)) x_1 / ↑(n.succ * n !)) • iteratedDerivWithin (n + 1) f [[x₀, x]] x_1)
Module: Mathlib.Analysis.Calculus.Taylor

Goal state before:
pp: case e'_2.x.e_f
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
t : ℝ
⊢ ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t =
    -(↑(n + 1) * (x - t) ^ (n + 1 - 1) * -(fun x ↦ 1) t / ↑(n.succ * n !)) • iteratedDerivWithin (n + 1) f [[x₀, x]] t

Tactic:
congr

Goal state after:
case e'_2.x.e_f.e_a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
t : ℝ
⊢ (x - t) ^ n / ↑n ! = -(↑(n + 1) * (x - t) ^ (n + 1 - 1) * -(fun x ↦ 1) t / ↑(n.succ * n !))
Module: Mathlib.Analysis.Calculus.Taylor

Goal state before:
pp: case e'_3
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
x✝¹ : ℝ
x✝ : x✝¹ ∈ uIoo x₀ x
h1 : min x₀ x < x✝¹
h2 : x✝¹ < max x₀ x
⊢ ((x - x✝¹) ^ (n + 1) / ((↑n + 1) * ↑n !)) • derivWithin (iteratedDerivWithin (n + 1) f [[x₀, x]]) [[x₀, x]] x✝¹ =
    (fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!) x✝¹ • deriv (fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t) x✝¹

Tactic:
congr

Goal state after:
case e'_3.e_a.e_a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
x✝¹ : ℝ
x✝ : x✝¹ ∈ uIoo x₀ x
h1 : min x₀ x < x✝¹
h2 : x✝¹ < max x₀ x
⊢ (↑n + 1) * ↑n ! = ↑(n + 1)!

case e'_3.e_a
F : Type u_3
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
f : ℝ → F
x x₀ : ℝ
this✝ : x₀ ≠ x
n : ℕ
ih :
  f x - taylorWithinEval f n [[x₀, x]] x₀ x =
    ∫ (t : ℝ) in x₀..x, ((x - t) ^ n / ↑n !) • iteratedDerivWithin (n + 1) f [[x₀, x]] t
hf :
  ∀ k ≤ n + 1,
    let u := fun t ↦ (x - t) ^ k / ↑k !;
    let v := fun t ↦ iteratedDerivWithin k f [[x₀, x]] t;
    ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
this :
  let u := fun t ↦ (x - t) ^ (n + 1) / ↑(n + 1)!;
  let v := fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t;
  ∫ (t : ℝ) in x₀..x, u t • deriv v t = u x • v x - u x₀ • v x₀ - ∫ (t : ℝ) in x₀..x, deriv u t • v t
x✝¹ : ℝ
x✝ : x✝¹ ∈ uIoo x₀ x
h1 : min x₀ x < x✝¹
h2 : x✝¹ < max x₀ x
⊢ derivWithin (iteratedDerivWithin (n + 1) f [[x₀, x]]) [[x₀, x]] x✝¹ =
    deriv (fun t ↦ iteratedDerivWithin (n + 1) f [[x₀, x]] t) x✝¹
Module: Mathlib.MeasureTheory.Function.AbsolutelyContinuous

Goal state before:
pp: F : Type u_2
inst✝ : SeminormedAddCommGroup F
a✝ b✝ : ℝ
f : ℝ → F
a b : ℝ
hf :
  ∀ ε > 0,
    ∃ δ > 0,
      ∀ E ∈ disjWithin a b,
        ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ →
          ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < ε
hab₀ : a ≤ b
hab : a < b
δ : ℝ
hδ₁ : δ > 0
hδ₂ :
  ∀ E ∈ disjWithin a b,
    ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ → ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < 1
hab₁ : 0 < b - a
n : ℕ
hn : 1 / (↑n + 1) < δ / (b - a)
δ' : ℝ := (b - a) / (↑n + 1)
hδ₃ : δ' < δ
h_mono : Monotone fun i ↦ a + ↑i * δ'
v_sum : eVariationOn f (Icc a b) = ∑ i ∈ Finset.range (n + 1), eVariationOn f (Icc (a + ↑i * δ') (a + (↑i + 1) * δ'))
x y : ℝ
x✝³ : a ≤ x
x✝² : x ≤ y
x✝¹ : y < x + δ
x✝ : y ≤ b
p : ℕ × { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ Icc x y }
hp₁ : Monotone ↑p.2
hp₂ : ∀ (i : ℕ), ↑p.2 i ∈ Icc x y
this : ↑p.2 p.1 - ↑p.2 0 < δ
⊢ ∑ i ∈ Finset.range (p.1, fun i ↦ (↑p.2 i, ↑p.2 (i + 1))).1,
      dist ((p.1, fun i ↦ (↑p.2 i, ↑p.2 (i + 1))).2 i).1 ((p.1, fun i ↦ (↑p.2 i, ↑p.2 (i + 1))).2 i).2 =
    ∑ i ∈ Finset.range p.1, (↑p.2 (i + 1) - ↑p.2 i)

Tactic:
congr

Goal state after:
case e_f
F : Type u_2
inst✝ : SeminormedAddCommGroup F
a✝ b✝ : ℝ
f : ℝ → F
a b : ℝ
hf :
  ∀ ε > 0,
    ∃ δ > 0,
      ∀ E ∈ disjWithin a b,
        ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ →
          ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < ε
hab₀ : a ≤ b
hab : a < b
δ : ℝ
hδ₁ : δ > 0
hδ₂ :
  ∀ E ∈ disjWithin a b,
    ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ → ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < 1
hab₁ : 0 < b - a
n : ℕ
hn : 1 / (↑n + 1) < δ / (b - a)
δ' : ℝ := (b - a) / (↑n + 1)
hδ₃ : δ' < δ
h_mono : Monotone fun i ↦ a + ↑i * δ'
v_sum : eVariationOn f (Icc a b) = ∑ i ∈ Finset.range (n + 1), eVariationOn f (Icc (a + ↑i * δ') (a + (↑i + 1) * δ'))
x y : ℝ
x✝³ : a ≤ x
x✝² : x ≤ y
x✝¹ : y < x + δ
x✝ : y ≤ b
p : ℕ × { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ Icc x y }
hp₁ : Monotone ↑p.2
hp₂ : ∀ (i : ℕ), ↑p.2 i ∈ Icc x y
this : ↑p.2 p.1 - ↑p.2 0 < δ
⊢ (fun i ↦ dist ((p.1, fun i ↦ (↑p.2 i, ↑p.2 (i + 1))).2 i).1 ((p.1, fun i ↦ (↑p.2 i, ↑p.2 (i + 1))).2 i).2) = fun i ↦
    ↑p.2 (i + 1) - ↑p.2 i
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
H : √((1 - x) ^ 2 + y ^ 2) ≤ 1 - x / 2
⊢ √(x ^ 2 + (s * x) ^ 2) = √((1 + s ^ 2) * x ^ 2)

Tactic:
congr

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

Tactic:
by congr; ring

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

Goal state before:
pp: F : Type u_2
inst✝ : SeminormedAddCommGroup F
a✝ b✝ : ℝ
f : ℝ → F
a b : ℝ
hf :
  ∀ ε > 0,
    ∃ δ > 0,
      ∀ E ∈ disjWithin a b,
        ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ →
          ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < ε
hab₀ : a ≤ b
hab : a < b
δ : ℝ
hδ₁ : δ > 0
hδ₂ :
  ∀ E ∈ disjWithin a b,
    ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ → ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < 1
hab₁ : 0 < b - a
n : ℕ
hn : 1 / (↑n + 1) < δ / (b - a)
δ' : ℝ := (b - a) / (↑n + 1)
hδ₃ : δ' < δ
h_mono : Monotone fun i ↦ a + ↑i * δ'
v_sum : eVariationOn f (Icc a b) = ∑ i ∈ Finset.range (n + 1), eVariationOn f (Icc (a + ↑i * δ') (a + (↑i + 1) * δ'))
x y : ℝ
x✝³ : a ≤ x
x✝² : x ≤ y
x✝¹ : y < x + δ
x✝ : y ≤ b
p : ℕ × { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ Icc x y }
hp₁ : Monotone ↑p.2
hp₂ : ∀ (i : ℕ), ↑p.2 i ∈ Icc x y
vf : ∑ i ∈ Finset.range p.1, dist (f (↑p.2 i)) (f (↑p.2 (i + 1))) < 1
⊢ ∑ x_1 ∈ Finset.range p.1, dist (f (↑p.2 (x_1 + 1))) (f (↑p.2 x_1)) =
    ∑ i ∈ Finset.range p.1, dist (f (↑p.2 i)) (f (↑p.2 (i + 1)))

Tactic:
congr

Goal state after:
case e_f
F : Type u_2
inst✝ : SeminormedAddCommGroup F
a✝ b✝ : ℝ
f : ℝ → F
a b : ℝ
hf :
  ∀ ε > 0,
    ∃ δ > 0,
      ∀ E ∈ disjWithin a b,
        ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ →
          ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < ε
hab₀ : a ≤ b
hab : a < b
δ : ℝ
hδ₁ : δ > 0
hδ₂ :
  ∀ E ∈ disjWithin a b,
    ∑ i ∈ Finset.range E.1, dist (E.2 i).1 (E.2 i).2 < δ → ∑ i ∈ Finset.range E.1, dist (f (E.2 i).1) (f (E.2 i).2) < 1
hab₁ : 0 < b - a
n : ℕ
hn : 1 / (↑n + 1) < δ / (b - a)
δ' : ℝ := (b - a) / (↑n + 1)
hδ₃ : δ' < δ
h_mono : Monotone fun i ↦ a + ↑i * δ'
v_sum : eVariationOn f (Icc a b) = ∑ i ∈ Finset.range (n + 1), eVariationOn f (Icc (a + ↑i * δ') (a + (↑i + 1) * δ'))
x y : ℝ
x✝³ : a ≤ x
x✝² : x ≤ y
x✝¹ : y < x + δ
x✝ : y ≤ b
p : ℕ × { u // Monotone u ∧ ∀ (i : ℕ), u i ∈ Icc x y }
hp₁ : Monotone ↑p.2
hp₂ : ∀ (i : ℕ), ↑p.2 i ∈ Icc x y
vf : ∑ i ∈ Finset.range p.1, dist (f (↑p.2 i)) (f (↑p.2 (i + 1))) < 1
⊢ (fun x_1 ↦ dist (f (↑p.2 (x_1 + 1))) (f (↑p.2 x_1))) = fun i ↦ dist (f (↑p.2 i)) (f (↑p.2 (i + 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
hab : a ≤ b
d : ℝ
hd : a ≤ d ∧ d ≤ b
r : ℝ
hr : r > 0
had : a ≤ d
hdb : d < b
hf₀ : ∀ᵐ (x : ℝ), x ∈ Ioo d b → HasDerivAt f 0 x
hfdb' : 0 < r / (b - d)
u : Set (ℝ × ℝ)
hu₁ : ∀ z ∈ u, (d < z.1 ∧ z.1 < z.2 ∧ z.2 < b) ∧ dist (slope f z.1 z.2) 0 < r / (b - d)
hu₂ : u.PairwiseDisjoint fun z ↦ Icc z.1 z.2
hu₃ : HasSum (fun z ↦ (↑z).2 - (↑z).1) (b - d)
g : ↑u → ℝ := fun z ↦ dist (f (↑z).1) (f (↑z).2)
g_nonneg : 0 ≤ g
s : Finset ↑u
z : ↑u
hz : z ∈ s
slope_bound : dist (slope f (↑z).1 (↑z).2) 0 ≤ r / (b - d)
this : 0 < (↑z).2 - (↑z).1
⊢ ‖f (↑z).1 - f (↑z).2‖ ≤ ((↑z).2 - (↑z).1) * ‖((↑z).2 - (↑z).1)⁻¹ • (f (↑z).2 - f (↑z).1)‖

Tactic:
← Real.norm_of_nonneg this.le

Goal state after:
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
hab : a ≤ b
d : ℝ
hd : a ≤ d ∧ d ≤ b
r : ℝ
hr : r > 0
had : a ≤ d
hdb : d < b
hf₀ : ∀ᵐ (x : ℝ), x ∈ Ioo d b → HasDerivAt f 0 x
hfdb' : 0 < r / (b - d)
u : Set (ℝ × ℝ)
hu₁ : ∀ z ∈ u, (d < z.1 ∧ z.1 < z.2 ∧ z.2 < b) ∧ dist (slope f z.1 z.2) 0 < r / (b - d)
hu₂ : u.PairwiseDisjoint fun z ↦ Icc z.1 z.2
hu₃ : HasSum (fun z ↦ (↑z).2 - (↑z).1) (b - d)
g : ↑u → ℝ := fun z ↦ dist (f (↑z).1) (f (↑z).2)
g_nonneg : 0 ≤ g
s : Finset ↑u
z : ↑u
hz : z ∈ s
slope_bound : dist (slope f (↑z).1 (↑z).2) 0 ≤ r / (b - d)
this : 0 < (↑z).2 - (↑z).1
⊢ ‖f (↑z).1 - f (↑z).2‖ ≤ ‖(↑z).2 - (↑z).1‖ * ‖((↑z).2 - (↑z).1)⁻¹ • (f (↑z).2 - f (↑z).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
hab : a ≤ b
d : ℝ
hd : a ≤ d ∧ d ≤ b
r : ℝ
hr : r > 0
had : a ≤ d
hdb : d < b
hf₀ : ∀ᵐ (x : ℝ), x ∈ Ioo d b → HasDerivAt f 0 x
hfdb' : 0 < r / (b - d)
u : Set (ℝ × ℝ)
hu₁ : ∀ z ∈ u, (d < z.1 ∧ z.1 < z.2 ∧ z.2 < b) ∧ dist (slope f z.1 z.2) 0 < r / (b - d)
hu₂ : u.PairwiseDisjoint fun z ↦ Icc z.1 z.2
hu₃ : HasSum (fun z ↦ (↑z).2 - (↑z).1) (b - d)
g : ↑u → ℝ := fun z ↦ dist (f (↑z).1) (f (↑z).2)
g_nonneg : 0 ≤ g
s : Finset ↑u
z : ↑u
hz : z ∈ s
slope_bound : dist (slope f (↑z).1 (↑z).2) 0 ≤ r / (b - d)
this : 0 < (↑z).2 - (↑z).1
⊢ ‖f (↑z).1 - f (↑z).2‖ ≤ ‖(↑z).2 - (↑z).1‖ * ‖((↑z).2 - (↑z).1)⁻¹ • (f (↑z).2 - f (↑z).1)‖

Tactic:
simp only [norm_smul, Real.norm_eq_abs, norm_inv]

Goal state after:
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
hab : a ≤ b
d : ℝ
hd : a ≤ d ∧ d ≤ b
r : ℝ
hr : r > 0
had : a ≤ d
hdb : d < b
hf₀ : ∀ᵐ (x : ℝ), x ∈ Ioo d b → HasDerivAt f 0 x
hfdb' : 0 < r / (b - d)
u : Set (ℝ × ℝ)
hu₁ : ∀ z ∈ u, (d < z.1 ∧ z.1 < z.2 ∧ z.2 < b) ∧ dist (slope f z.1 z.2) 0 < r / (b - d)
hu₂ : u.PairwiseDisjoint fun z ↦ Icc z.1 z.2
hu₃ : HasSum (fun z ↦ (↑z).2 - (↑z).1) (b - d)
g : ↑u → ℝ := fun z ↦ dist (f (↑z).1) (f (↑z).2)
g_nonneg : 0 ≤ g
s : Finset ↑u
z : ↑u
hz : z ∈ s
slope_bound : dist (slope f (↑z).1 (↑z).2) 0 ≤ r / (b - d)
this : 0 < (↑z).2 - (↑z).1
⊢ ‖f (↑z).1 - f (↑z).2‖ ≤ |(↑z).2 - (↑z).1| * (|(↑z).2 - (↑z).1|⁻¹ * ‖f (↑z).2 - f (↑z).1‖)
Module: Mathlib.Analysis.Normed.Module.Ray

Goal state before:
pp: case inr
F : Type u_2
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℝ F
x y : F
h : ‖x‖ = ‖y‖
hy : y ≠ 0
⊢ SameRay ℝ x y ↔ x = y

Tactic:
exact ⟨fun hxy => norm_injOn_ray_right hy hxy SameRay.rfl h, fun hxy => hxy ▸ SameRay.rfl⟩

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

Goal state before:
pp: E : Type u_2
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
h : ∀ (x y : E), ‖x‖ = 1 → ‖y‖ = 1 → x ≠ y → ∃ a b, 0 ≤ a ∧ 0 ≤ b ∧ a + b = 1 ∧ ‖a • x + b • y‖ ≠ 1
x : E
hx : ‖x‖ = 1
⊢ ∀ ⦃y : E⦄, ‖y‖ = 1 → x ≠ y → ([x -[ℝ] y] \ sphere 0 1).Nonempty

Tactic:
y

Goal state after:
E : Type u_2
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℝ E
h : ∀ (x y : E), ‖x‖ = 1 → ‖y‖ = 1 → x ≠ y → ∃ a b, 0 ≤ a ∧ 0 ≤ b ∧ a + b = 1 ∧ ‖a • x + b • y‖ ≠ 1
x : E
hx : ‖x‖ = 1
y : E
⊢ ‖y‖ = 1 → x ≠ y → ([x -[ℝ] y] \ sphere 0 1).Nonempty
Module: Mathlib.Analysis.Convex.Uniform

Goal state before:
pp: case inr.inr
E : Type u_1
inst✝² : SeminormedAddCommGroup E
inst✝¹ : UniformConvexSpace E
ε : ℝ
inst✝ : NormedSpace ℝ E
hε : 0 < ε
hε' : 0 < ε / 3
δ : ℝ
hδ : 0 < δ
h : ∀ ⦃x : E⦄, ‖x‖ = 1 → ∀ ⦃y : E⦄, ‖y‖ = 1 → ε / 3 ≤ ‖x - y‖ → ‖x + y‖ ≤ 2 - δ
δ' : ℝ := min (1 / 2) (min (ε / 3) (δ / 3))
x : E
hx : ‖x‖ ≤ 1
y : E
hy : ‖y‖ ≤ 1
hxy : ε ≤ ‖x - y‖
hx' : 1 - δ' < ‖x‖
hy' : 1 - δ' < ‖y‖
hδ' : 0 < 1 - δ'
h₁ : ∀ (z : E), 1 - δ' < ‖z‖ → ‖‖z‖⁻¹ • z‖ = 1
h₂ : ∀ (z : E), ‖z‖ ≤ 1 → 1 - δ' ≤ ‖z‖ → ‖‖z‖⁻¹ • z - z‖ ≤ δ'
x' : E := ‖x‖⁻¹ • x
⊢ ‖x + y‖ ≤ 2 - δ'

Tactic:
set y' := ‖y‖⁻¹ • y

Goal state after:
case inr.inr
E : Type u_1
inst✝² : SeminormedAddCommGroup E
inst✝¹ : UniformConvexSpace E
ε : ℝ
inst✝ : NormedSpace ℝ E
hε : 0 < ε
hε' : 0 < ε / 3
δ : ℝ
hδ : 0 < δ
h : ∀ ⦃x : E⦄, ‖x‖ = 1 → ∀ ⦃y : E⦄, ‖y‖ = 1 → ε / 3 ≤ ‖x - y‖ → ‖x + y‖ ≤ 2 - δ
δ' : ℝ := min (1 / 2) (min (ε / 3) (δ / 3))
x : E
hx : ‖x‖ ≤ 1
y : E
hy : ‖y‖ ≤ 1
hxy : ε ≤ ‖x - y‖
hx' : 1 - δ' < ‖x‖
hy' : 1 - δ' < ‖y‖
hδ' : 0 < 1 - δ'
h₁ : ∀ (z : E), 1 - δ' < ‖z‖ → ‖‖z‖⁻¹ • z‖ = 1
h₂ : ∀ (z : E), ‖z‖ ≤ 1 → 1 - δ' ≤ ‖z‖ → ‖‖z‖⁻¹ • z - z‖ ≤ δ'
x' : E := ‖x‖⁻¹ • x
y' : E := ‖y‖⁻¹ • y
⊢ ‖x + y‖ ≤ 2 - δ'
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: D : Set ℝ
hD : Convex ℝ D
f : ℝ → ℝ
hf : ContinuousOn f D
hf' : DifferentiableOn ℝ f (interior D)
hf'_mono : MonotoneOn (deriv f) (interior D)
x : ℝ
⊢ ∀ {y z : ℝ}, x ∈ D → z ∈ D → x < y → y < z → (f y - f x) / (y - x) ≤ (f z - f y) / (z - y)

Tactic:
y

Goal state after:
D : Set ℝ
hD : Convex ℝ D
f : ℝ → ℝ
hf : ContinuousOn f D
hf' : DifferentiableOn ℝ f (interior D)
hf'_mono : MonotoneOn (deriv f) (interior D)
x y : ℝ
⊢ ∀ {z : ℝ}, x ∈ D → z ∈ D → x < y → y < z → (f y - f x) / (y - x) ≤ (f z - f y) / (z - y)
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Complex

Goal state before:
pp: case inr
k l : ℤ
t : ∀ (n : ℤ), tan (↑n * ↑π / 2) = 0
hx : tan (↑(2 * k + 1) * ↑π / 2) = 0
hy : tan (↑(2 * l + 1) * ↑π / 2) = 0
hxy : tan (↑(2 * k + 1 + (2 * l + 1)) * ↑π / 2) = 0
⊢ tan ((2 * ↑k + 1) * ↑π / 2 + (2 * ↑l + 1) * ↑π / 2) =
    (tan ((2 * ↑k + 1) * ↑π / 2) + tan ((2 * ↑l + 1) * ↑π / 2)) /
      (1 - tan ((2 * ↑k + 1) * ↑π / 2) * tan ((2 * ↑l + 1) * ↑π / 2))

Tactic:
simp only [Int.cast_add, Int.cast_two, Int.cast_mul, Int.cast_one] at hx hy hxy

Goal state after:
case inr
k l : ℤ
t : ∀ (n : ℤ), tan (↑n * ↑π / 2) = 0
hx : tan ((2 * ↑k + 1) * ↑π / 2) = 0
hy : tan ((2 * ↑l + 1) * ↑π / 2) = 0
hxy : tan ((2 * ↑k + 1 + (2 * ↑l + 1)) * ↑π / 2) = 0
⊢ tan ((2 * ↑k + 1) * ↑π / 2 + (2 * ↑l + 1) * ↑π / 2) =
    (tan ((2 * ↑k + 1) * ↑π / 2) + tan ((2 * ↑l + 1) * ↑π / 2)) /
      (1 - tan ((2 * ↑k + 1) * ↑π / 2) * tan ((2 * ↑l + 1) * ↑π / 2))
Module: Mathlib.Analysis.Complex.AbsMax

Goal state before:
pp: E : Type u
inst✝¹ : NormedAddCommGroup E
inst✝ : NormedSpace ℂ E
f : E → ℂ
c : E
hf : ∀ᶠ (z : E) in 𝓝 c, DifferentiableAt ℂ f z
hc : IsLocalMin (norm ∘ f) c
⊢ (∀ᶠ (z : E) in 𝓝 c, f z = f c) ∨ f c = 0

Tactic:
by
  refine or_iff_not_imp_right.mpr fun h => ?_
  have h1 : ∀ᶠ z in 𝓝 c, f z ≠ 0 := hf.self_of_nhds.continuousAt.eventually_ne h
  have h2 : IsLocalMax (norm ∘ f)⁻¹ c := hc.inv (h1.mono fun z => norm_pos_iff.mpr)
  have h3 : IsLocalMax (norm ∘ f⁻¹) c := by refine h2.congr (Eventually.of_forall ?_); simp
  have h4 : ∀ᶠ z in 𝓝 c, DifferentiableAt ℂ f⁻¹ z := by filter_upwards [hf, h1] with z h using h.inv
  filter_upwards [eventually_eq_of_isLocalMax_norm h4 h3] with z using inv_inj.mp

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

Goal state before:
pp: f : ℕ → ℝ
l : ℝ
m : Filter.map ofReal (𝓝 l) ≤ 𝓝 ↑l
h :
  ∀ ε > 0,
    ∃ δ > 0, ∀ ⦃x : ℝ⦄, x ∈ Set.Iio 1 → dist x 1 < δ → dist (((fun z ↦ ∑' (n : ℕ), ↑(f n) * z ^ n) ∘ ofReal) x) ↑l < ε
a✝⁴ : ℝ
a✝³ : a✝⁴ > 0
x✝ a✝² : ℝ
a✝¹ : a✝² ∈ Set.Iio 1
a✝ : dist a✝² 1 < x✝
⊢ dist (∑' (n : ℕ), f n * a✝² ^ n) l = dist (((fun z ↦ ∑' (n : ℕ), ↑(f n) * z ^ n) ∘ ofReal) a✝²) ↑l

Tactic:
Function.comp_apply,

Goal state after:
f : ℕ → ℝ
l : ℝ
m : Filter.map ofReal (𝓝 l) ≤ 𝓝 ↑l
h :
  ∀ ε > 0,
    ∃ δ > 0, ∀ ⦃x : ℝ⦄, x ∈ Set.Iio 1 → dist x 1 < δ → dist (((fun z ↦ ∑' (n : ℕ), ↑(f n) * z ^ n) ∘ ofReal) x) ↑l < ε
a✝⁴ : ℝ
a✝³ : a✝⁴ > 0
x✝ a✝² : ℝ
a✝¹ : a✝² ∈ Set.Iio 1
a✝ : dist a✝² 1 < x✝
⊢ dist (∑' (n : ℕ), f n * a✝² ^ n) l = dist (∑' (n : ℕ), ↑(f n) * ↑a✝² ^ n) ↑l
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Arctan

Goal state before:
pp: x : ℝ
h : x ∈ Ioo (-1) 1
⊢ arcsin x = arctan (x / √(1 - x ^ 2))

Tactic:
rw_mod_cast [arctan_eq_arcsin, div_pow, sq_sqrt, one_add_div, div_div, ← sqrt_mul,
    mul_div_cancel₀, sub_add_cancel, sqrt_one, div_one]

Goal state after:
case hb
x : ℝ
h : x ∈ Ioo (↑(Int.negSucc 0)) 1
⊢ 1 - x ^ 2 ≠ 0

case hx
x : ℝ
h : x ∈ Ioo (↑(Int.negSucc 0)) 1
⊢ 0 ≤ 1 - x ^ 2

x : ℝ
h : x ∈ Ioo (↑(Int.negSucc 0)) 1
⊢ 1 - x ^ 2 ≠ 0

x : ℝ
h : x ∈ Ioo (↑(Int.negSucc 0)) 1
⊢ 0 ≤ 1 - x ^ 2
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Arctan

Goal state before:
pp: x y : ℝ
h : tan x = y
hx : x ∈ Ioo (-(π / 2)) (π / 2)
⊢ tan (arctan y) = tan x

Tactic:
rw [tan_arctan, h]

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

Goal state before:
pp: x y : ℝ
h : x * y < 1
⊢ arctan (tan (arctan x + arctan y)) = arctan ((x + y) / (1 - x * y))

Tactic:
congr

Goal state after:
x y : ℝ
h : x * y < 1
⊢ tan (arctan x + arctan y) = (x + y) / (1 - x * y)
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: S : Set ℝ
f : ℝ → ℝ
hfc : ConvexOn ℝ S f
x : ℝ
hxs : x ∈ interior S
⊢ ∀ ⦃b : ℝ⦄, b ∈ interior S → x ≤ b → (fun x ↦ derivWithin f (Ioi x) x) x ≤ (fun x ↦ derivWithin f (Ioi x) x) b

Tactic:
y

Goal state after:
S : Set ℝ
f : ℝ → ℝ
hfc : ConvexOn ℝ S f
x : ℝ
hxs : x ∈ interior S
y : ℝ
⊢ y ∈ interior S → x ≤ y → (fun x ↦ derivWithin f (Ioi x) x) x ≤ (fun x ↦ derivWithin f (Ioi x) x) y
Module: Mathlib.Analysis.Convex.Deriv

Goal state before:
pp: S : Set ℝ
f : ℝ → ℝ
hfc : ConvexOn ℝ S f
x : ℝ
hxs : x ∈ interior S
⊢ ∀ ⦃b : ℝ⦄, b ∈ interior S → x ≤ b → (fun x ↦ derivWithin f (Iio x) x) x ≤ (fun x ↦ derivWithin f (Iio x) x) b

Tactic:
y

Goal state after:
S : Set ℝ
f : ℝ → ℝ
hfc : ConvexOn ℝ S f
x : ℝ
hxs : x ∈ interior S
y : ℝ
⊢ y ∈ interior S → x ≤ y → (fun x ↦ derivWithin f (Iio x) x) x ≤ (fun x ↦ derivWithin f (Iio x) x) y