mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Algebra.Order.CauSeq.BigOperators

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
⊢ max N M + 1 < 2 * (max N M + 1)

Tactic:
two_mul

Goal state after:
α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
⊢ max N M + 1 < max N M + 1 + (max N M + 1)
Module: Mathlib.Analysis.Complex.Exponential

Goal state before:
pp: x y : ℂ
j m : ℕ
x✝ : m ∈ range j
I : ℕ
hi : I ∈ range (m + 1)
h₁ : ↑(m.choose I) ≠ 0
h₂ : m.choose I * I.factorial * (m - I).factorial = m.factorial
⊢ x ^ I * y ^ (m - I) * ↑(m.choose I) * ((↑(m.choose I) * ↑I.factorial)⁻¹ * (↑(m - I).factorial)⁻¹) =
    x ^ I / ↑I.factorial * (y ^ (m - I) / ↑(m - I).factorial)

Tactic:
mul_inv

Goal state after:
x y : ℂ
j m : ℕ
x✝ : m ∈ range j
I : ℕ
hi : I ∈ range (m + 1)
h₁ : ↑(m.choose I) ≠ 0
h₂ : m.choose I * I.factorial * (m - I).factorial = m.factorial
⊢ x ^ I * y ^ (m - I) * ↑(m.choose I) * ((↑(m.choose I))⁻¹ * (↑I.factorial)⁻¹ * (↑(m - I).factorial)⁻¹) =
    x ^ I / ↑I.factorial * (y ^ (m - I) / ↑(m - I).factorial)
Module: Mathlib.Algebra.Order.CauSeq.BigOperators

Goal state before:
pp: case hbc
α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
hNMK : max N M + 1 < K
hKN : N < K
m : ℕ
hmJ : m ∈ range (max N M + 1)
⊢ m + N ≤ 2 * (max N M + 1)

Tactic:
two_mul

Goal state after:
case hbc
α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
hNMK : max N M + 1 < K
hKN : N < K
m : ℕ
hmJ : m ∈ range (max N M + 1)
⊢ m + N ≤ max N M + 1 + (max N M + 1)
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x : ℂ
⊢ cexp x + cexp x = 2 * cexp x

Tactic:
two_mul

Goal state after:
x : ℂ
⊢ cexp x + cexp x = cexp x + cexp x
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x : ℂ
⊢ cexp (-x) + cexp (-x) = 2 * cexp (-x)

Tactic:
two_mul

Goal state after:
x : ℂ
⊢ cexp (-x) + cexp (-x) = cexp (-x) + cexp (-x)
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x : ℂ
h : I * sin (x * I) = -sinh x
⊢ sin (x * I) = -(I * sin (x * I)) * I

Tactic:
apply Complex.ext

Goal state after:
case a
x : ℂ
h : I * sin (x * I) = -sinh x
⊢ (sin (x * I)).re = (-(I * sin (x * I)) * I).re

case a
x : ℂ
h : I * sin (x * I) = -sinh x
⊢ (sin (x * I)).im = (-(I * sin (x * I)) * I).im
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x y : ℂ
⊢ sin (x + y * I) = sin x * cosh y + cos x * sinh y * I

Tactic:
rw [sin_add, cos_mul_I, sin_mul_I, mul_assoc]

Goal state after:
Module: Mathlib.Analysis.Asymptotics.Lemmas

Goal state before:
pp: α : Type u_1
E : Type u_3
F'' : Type u_10
inst✝¹ : Norm E
inst✝ : NormedAddCommGroup F''
f : α → E
g'' : α → F''
h : f =O[cofinite] g''
C : ℝ
C₀ : C > 0
hC : IsBigOWith C cofinite f g''
⊢ ∃ C > 0, ∀ ⦃x : α⦄, g'' x ≠ 0 → ‖f x‖ ≤ C * ‖g'' x‖

Tactic:
rw [IsBigOWith_def, eventually_cofinite] at hC

Goal state after:
α : Type u_1
E : Type u_3
F'' : Type u_10
inst✝¹ : Norm E
inst✝ : NormedAddCommGroup F''
f : α → E
g'' : α → F''
h : f =O[cofinite] g''
C : ℝ
C₀ : C > 0
hC : {x | ¬‖f x‖ ≤ C * ‖g'' x‖}.Finite
⊢ ∃ C > 0, ∀ ⦃x : α⦄, g'' x ≠ 0 → ‖f x‖ ≤ C * ‖g'' x‖
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x : ℂ
⊢ cos x ^ 2 + cos x ^ 2 - 1 = 2 * cos x ^ 2 - 1

Tactic:
two_mul

Goal state after:
x : ℂ
⊢ cos x ^ 2 + cos x ^ 2 - 1 = cos x ^ 2 + cos x ^ 2 - 1
Module: Mathlib.Analysis.Complex.Trigonometric

Goal state before:
pp: x : ℂ
hx : ‖x‖ ≤ 1
⊢ ‖(cexp (-x * I) - ∑ m ∈ range 4, (-x * I) ^ m / ↑m.factorial) / 2 +
        (cexp (x * I) - ∑ m ∈ range 4, (x * I) ^ m / ↑m.factorial) / 2‖ ≤
    ‖cexp (-x * I) - ∑ m ∈ range 4, (-x * I) ^ m / ↑m.factorial‖ / 2 +
      ‖cexp (x * I) - ∑ m ∈ range 4, (x * I) ^ m / ↑m.factorial‖ / 2

Tactic:
grw [norm_add_le]

Goal state after:
x : ℂ
hx : ‖x‖ ≤ 1
⊢ ‖(cexp (-x * I) - ∑ m ∈ range 4, (-x * I) ^ m / ↑m.factorial) / 2‖ +
      ‖(cexp (x * I) - ∑ m ∈ range 4, (x * I) ^ m / ↑m.factorial) / 2‖ ≤
    ‖cexp (-x * I) - ∑ m ∈ range 4, (-x * I) ^ m / ↑m.factorial‖ / 2 +
      ‖cexp (x * I) - ∑ m ∈ range 4, (x * I) ^ m / ↑m.factorial‖ / 2
Module: Mathlib.Analysis.Complex.Exponential

Goal state before:
pp: x : ℂ
n j : ℕ
hj : j ≥ n
⊢ ‖∑ m ∈ Ico n j, x ^ m / ↑m.factorial‖ = ‖∑ m ∈ Ico n j, x ^ n * (x ^ (m - n) / ↑m.factorial)‖

Tactic:
refine congr_arg norm (sum_congr rfl fun m hm => ?_)
      rw [mem_Ico] at hm
      rw [← mul_div_assoc, ← pow_add, add_tsub_cancel_of_le hm.1]

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

Goal state before:
pp: x y : ℝ
⊢ cosh (x + y) = cosh x * cosh y + sinh x * sinh y

Tactic:
rw [← ofReal_inj]; simp [cosh_add]

Goal state after:
Module: Mathlib.Algebra.Order.CauSeq.BigOperators

Goal state before:
pp: α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
hNMK : max N M + 1 < K
hKN : N < K
hsumlesum :
  ∑ i ∈ range (max N M + 1), abv (f i) * abv (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) ≤
    ∑ i ∈ range (max N M + 1), abv (f i) * (ε / (2 * P))
hsumltP : ∑ n ∈ range (max N M + 1), abv (f n) < P
⊢ ∑ i ∈ range K with max N M + 1 ≤ i, abv (f i) * (2 * Q) < ε / (4 * Q) * (2 * Q)

Tactic:
rw [← sum_mul, ← sum_range_sub_sum_range (le_of_lt hNMK)]

Goal state after:
α : Type u_1
β : Type u_2
inst✝⁴ : Field α
inst✝³ : LinearOrder α
inst✝² : IsStrictOrderedRing α
inst✝¹ : Ring β
abv : β → α
inst✝ : IsAbsoluteValue abv
f g : ℕ → β
ha : IsCauSeq abs fun m ↦ ∑ n ∈ range m, abv (f n)
hb : IsCauSeq abv fun m ↦ ∑ n ∈ range m, g n
ε : α
ε0 : 0 < ε
P : α
hP : ∀ (i : ℕ), |∑ n ∈ range i, abv (f n)| < P
Q : α
hQ : ∀ (i : ℕ), abv (∑ n ∈ range i, g n) < Q
hP0 : 0 < P
hPε0 : 0 < ε / (2 * P)
N : ℕ
hN : ∀ j ≥ N, ∀ k ≥ N, abv (∑ n ∈ range j, g n - ∑ n ∈ range k, g n) < ε / (2 * P)
hQε0 : 0 < ε / (4 * Q)
M : ℕ
hM : ∀ j ≥ M, ∀ k ≥ M, |∑ n ∈ range j, abv (f n) - ∑ n ∈ range k, abv (f n)| < ε / (4 * Q)
K : ℕ
hK : K ≥ 2 * (max N M + 1)
h₁ : ∑ m ∈ range K, ∑ k ∈ range (m + 1), f k * g (m - k) = ∑ m ∈ range K, ∑ n ∈ range (K - m), f m * g n
h₂ : (fun i ↦ ∑ k ∈ range (K - i), f i * g k) = fun i ↦ f i * ∑ k ∈ range (K - i), g k
h₃ :
  ∑ i ∈ range K, f i * ∑ k ∈ range (K - i), g k =
    ∑ i ∈ range K, f i * (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) + ∑ i ∈ range K, f i * ∑ k ∈ range K, g k
two_mul_two : 4 = 2 * 2
hQ0 : Q ≠ 0
h2Q0 : 2 * Q ≠ 0
hε : ε / (2 * P) * P + ε / (4 * Q) * (2 * Q) = ε
hNMK : max N M + 1 < K
hKN : N < K
hsumlesum :
  ∑ i ∈ range (max N M + 1), abv (f i) * abv (∑ k ∈ range (K - i), g k - ∑ k ∈ range K, g k) ≤
    ∑ i ∈ range (max N M + 1), abv (f i) * (ε / (2 * P))
hsumltP : ∑ n ∈ range (max N M + 1), abv (f n) < P
⊢ (∑ k ∈ range K, abv (f k) - ∑ k ∈ range (max N M + 1), abv (f k)) * (2 * Q) < ε / (4 * Q) * (2 * Q)
Module: Mathlib.Analysis.Asymptotics.Lemmas

Goal state before:
pp: α : Type u_1
E : Type u_2
F : Type u_3
inst✝² : TopologicalSpace α
s : Set α
f : α → E
inst✝¹ : NormedAddGroup E
inst✝ : SeminormedAddGroup F
hf : ContinuousOn f s
hC : ∀ i ∈ s, f i ≠ 0
c : F
x✝ : α
hx✝ : x✝ ∈ s
hs : IsCompact ((fun a ↦ ‖a‖) '' f '' s)
h_sInf : IsGLB ((fun a ↦ ‖a‖) '' f '' s) (sInf ((fun a ↦ ‖a‖) '' f '' s))
w✝ : E
hnormCx : (fun a ↦ ‖a‖) w✝ = sInf ((fun a ↦ ‖a‖) '' f '' s)
x : α
hx : x ∈ s
hCx : f x = w✝
⊢ 0 < (fun a ↦ ‖a‖) w✝

Tactic:
← hCx

Goal state after:
α : Type u_1
E : Type u_2
F : Type u_3
inst✝² : TopologicalSpace α
s : Set α
f : α → E
inst✝¹ : NormedAddGroup E
inst✝ : SeminormedAddGroup F
hf : ContinuousOn f s
hC : ∀ i ∈ s, f i ≠ 0
c : F
x✝ : α
hx✝ : x✝ ∈ s
hs : IsCompact ((fun a ↦ ‖a‖) '' f '' s)
h_sInf : IsGLB ((fun a ↦ ‖a‖) '' f '' s) (sInf ((fun a ↦ ‖a‖) '' f '' s))
w✝ : E
hnormCx : (fun a ↦ ‖a‖) w✝ = sInf ((fun a ↦ ‖a‖) '' f '' s)
x : α
hx : x ∈ s
hCx : f x = w✝
⊢ 0 < (fun a ↦ ‖a‖) (f x)
Module: Mathlib.Analysis.Normed.Group.Pointwise

Goal state before:
pp: E : Type u_1
inst✝ : SeminormedCommGroup E
δ : ℝ
s : Set E
⊢ s * ball 1 δ = thickening δ s

Tactic:
by
  rw [thickening_eq_biUnion_ball]
  convert! iUnion₂_mul (fun x (_ : x ∈ s) => { x }) (ball (1 : E) δ)
  · exact s.biUnion_of_singleton.symm
  ext x
  simp_rw [singleton_mul_ball, mul_one]

Goal state after:
Module: Mathlib.Analysis.Normed.Group.Pointwise

Goal state before:
pp: E : Type u_1
inst✝ : SeminormedCommGroup E
δ : ℝ
s : Set E
hs : IsCompact s
hδ : 0 ≤ δ
x : E
⊢ s / closedBall x δ = x⁻¹ • cthickening δ s

Tactic:
simp [div_eq_mul_inv, hs.mul_closedBall hδ]

Goal state after:
Module: Mathlib.Analysis.SpecificLimits.Normed

Goal state before:
pp: case pos
R : Type u_2
inst✝ : NormedRing R
k : ℕ
r₁ : R
r₂ : ℝ
h : ‖r₁‖ < r₂
h0 : r₁ = 0
n : ℕ
hn : 1 ≤ n
⊢ n ∈ {x | (fun x ↦ (fun _x ↦ 0) x = (fun n ↦ ↑n ^ k * r₁ ^ n) x) x}

Tactic:
simp [zero_pow (one_le_iff_ne_zero.1 hn), h0]

Goal state after:
Module: Mathlib.Analysis.Normed.Module.RCLike.Real

Goal state before:
pp: E : Type u_1
inst✝² : SeminormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : NontrivialTopology E
x : E
r : ℝ
⊢ (sphere x r).Nonempty ↔ 0 ≤ r

Tactic:
by
  refine ⟨fun h => nonempty_closedBall.1 (h.mono sphere_subset_closedBall), fun hr => ?_⟩
  obtain ⟨y, hy⟩ := exists_norm_eq E hr
  exact ⟨x + y, by simpa using hy⟩

Goal state after:
Module: Mathlib.Analysis.SpecificLimits.Normed

Goal state before:
pp: R : Type u_2
S : Type u_3
inst✝⁵ : Field R
inst✝⁴ : Field S
inst✝³ : LinearOrder S
inst✝² : TopologicalSpace S
inst✝¹ : IsStrictOrderedRing S
inst✝ : Archimedean S
_i : OrderTopology S
v : AbsoluteValue R S
a : R
ha : v a < 1
h_add : Tendsto (fun x ↦ 1 + v a ^ x) atTop (𝓝 (1 + 0))
⊢ Tendsto (fun n ↦ v (1 + a ^ n)) atTop (𝓝 1)

Tactic:
have h_sub := (tendsto_pow_atTop_nhds_zero_of_lt_one (v.nonneg _) ha).const_sub 1

Goal state after:
R : Type u_2
S : Type u_3
inst✝⁵ : Field R
inst✝⁴ : Field S
inst✝³ : LinearOrder S
inst✝² : TopologicalSpace S
inst✝¹ : IsStrictOrderedRing S
inst✝ : Archimedean S
_i : OrderTopology S
v : AbsoluteValue R S
a : R
ha : v a < 1
h_add : Tendsto (fun x ↦ 1 + v a ^ x) atTop (𝓝 (1 + 0))
h_sub : Tendsto (fun x ↦ 1 - v a ^ x) atTop (𝓝 (1 - 0))
⊢ Tendsto (fun n ↦ v (1 + a ^ n)) atTop (𝓝 1)
Module: Mathlib.Analysis.Normed.Module.Ball.Pointwise

Goal state before:
pp: E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x y : E
δ ε : ℝ
hδ : 0 ≤ δ
hε : 0 < ε
⊢ Disjoint (closedBall x δ) (ball y ε) ↔ δ + ε ≤ dist x y

Tactic:
disjoint_comm,

Goal state after:
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
x y : E
δ ε : ℝ
hδ : 0 ≤ δ
hε : 0 < ε
⊢ Disjoint (ball y ε) (closedBall x δ) ↔ δ + ε ≤ dist x y
Module: Mathlib.Analysis.SpecialFunctions.Trigonometric.Basic

Goal state before:
pp: x : ℝ
h0x : 0 < x
hxp : x < π / 2
⊢ 0 < tan x

Tactic:
by
  rw [tan_eq_sin_div_cos]
  exact div_pos (sin_pos_of_pos_of_lt_pi h0x (by linarith)) (cos_pos_of_mem_Ioo ⟨by linarith, hxp⟩)

Goal state after:
Module: Mathlib.Analysis.Normed.Module.Ball.Pointwise

Goal state before:
pp: case inr.coe
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
δ : ℝ
hδ : 0 < δ
s : Set E
x : E
hs : ENNReal.ofReal δ ≤ infEDist x s
z : E
hz : z ∈ s
r : NNReal
h : dist x z < δ + (↑r - δ)
hr : 0 < ↑r - δ
⊢ infEDist x (thickening δ s) + ENNReal.ofReal δ < ↑r

Tactic:
obtain ⟨y, hxy, hyz⟩ := exists_dist_lt_lt hr hδ h

Goal state after:
case inr.coe
E : Type u_2
inst✝¹ : SeminormedAddCommGroup E
inst✝ : NormedSpace ℝ E
δ : ℝ
hδ : 0 < δ
s : Set E
x : E
hs : ENNReal.ofReal δ ≤ infEDist x s
z : E
hz : z ∈ s
r : NNReal
h : dist x z < δ + (↑r - δ)
hr : 0 < ↑r - δ
y : E
hxy : dist x y < ↑r - δ
hyz : dist y z < δ
⊢ infEDist x (thickening δ s) + ENNReal.ofReal δ < ↑r
Module: Mathlib.Analysis.SpecificLimits.Normed

Goal state before:
pp: R : Type u_4
inst✝¹ : NormedRing R
inst✝ : HasSummableGeomSeries R
k : ℕ
r : R
hr : ‖r‖ < 1
⊢ HasSum (fun n ↦ ↑((n + k).choose k) * r ^ n) ((1 - r)⁻¹ʳ ^ (k + 1))

Tactic:
by
  induction k with
  | zero => simpa using hasSum_geom_series_inverse r hr
  | succ k ih =>
      have I1 : Summable (fun (n : ℕ) ↦ ‖(n + k).choose k * r ^ n‖) := by
        apply summable_norm_mul_geometric_of_norm_lt_one (k := k) hr
        apply isBigO_iff.2 ⟨2 ^ k, ?_⟩
        filter_upwards [Ioi_mem_atTop k] with n (hn : k < n)
        simp only [Real.norm_eq_abs, abs_cast, cast_pow, norm_pow]
        norm_cast
        calc (n + k).choose k
          _ ≤ (2 * n).choose k := choose_le_choose k (by lia)
          _ ≤ (2 * n) ^ k := Nat.choose_le_pow _ _
          _ = 2 ^ k * n ^ k := Nat.mul_pow 2 n k
      convert!
        hasSum_sum_range_mul_of_summable_norm' I1 ih.summable
          (summable_norm_geometric_of_norm_lt_one hr) (summable_geometric_of_norm_lt_one hr) with
        n
      · have : ∑ i ∈ Finset.range (n + 1), ↑((i + k).choose k) * r ^ i * r ^ (n - i) =
            ∑ i ∈ Finset.range (n + 1), ↑((i + k).choose k) * r ^ n := by
          apply Finset.sum_congr rfl (fun i hi ↦ ?_)
          simp only [Finset.mem_range] at hi
          rw [mul_assoc, ← pow_add, show i + (n - i) = n by lia]
        simp [this, ← sum_mul, ← Nat.cast_sum, sum_range_add_choose n k, add_assoc]
      · rw [ih.tsum_eq, (hasSum_geom_series_inverse r hr).tsum_eq, pow_succ]

Goal state after:
Module: Mathlib.Analysis.SpecificLimits.Normed

Goal state before:
pp: α : Type u_1
inst✝ : SeminormedAddCommGroup α
C : ℝ
u : ℕ → α
N : ℕ
r : ℝ
hr₀ : 0 < r
hr₁ : r < 1
h : ∀ n ≥ N, ‖u n‖ ≤ C * r ^ n
⊢ CauchySeq fun n ↦ ∑ k ∈ Finset.range (n + 1), u k

Tactic:
set v : ℕ → α := fun n ↦ if n < N then 0 else u n
  have hC : 0 ≤ C :=
    (mul_nonneg_iff_of_pos_right <| pow_pos hr₀ N).mp ((norm_nonneg _).trans <| h N <| le_refl N)
  have : ∀ n ≥ N, u n = v n := by
    intro n hn
    simp [v, if_neg (not_lt.mpr hn)]
  apply cauchySeq_sum_of_eventually_eq this
    (NormedAddCommGroup.cauchy_series_of_le_geometric' hr₁ _)
  · exact C
  intro n
  simp only [v]
  split_ifs with H
  · rw [norm_zero]
    exact mul_nonneg hC (pow_nonneg hr₀.le _)
  · push Not at H
    exact h _ H

Goal state after:
Module: Mathlib.Topology.Connected.PathConnected

Goal state before:
pp: X : Type u_1
inst✝ : TopologicalSpace X
motive : ZerothHomotopy X → Prop
mk : ∀ (x : X), motive (ZerothHomotopy.mk x)
x : ZerothHomotopy X
⊢ motive x

Tactic:
by
  obtain ⟨x, rfl⟩ := mk_surjective x
  exact mk x

Goal state after:
Module: Mathlib.Topology.CompactOpen

Goal state before:
pp: case mpr
X : Type u_2
Y : Type u_3
inst✝⁴ : TopologicalSpace X
inst✝³ : TopologicalSpace Y
inst✝² : WeaklyLocallyCompactSpace X
inst✝¹ : T2Space Y
ι : Type u_6
l : Filter ι
inst✝ : l.NeBot
F : ι → C(X, Y)
f : (s : Set X) → IsCompact s → C(↑s, Y)
hf : ∀ (s : Set X) (a : IsCompact s), Tendsto (fun i ↦ restrict s (F i)) l (𝓝 (f s a))
h :
  ∀ (s₁ : Set X) (hs₁ : IsCompact s₁) (s₂ : Set X) (hs₂ : IsCompact s₂) (x : X) (hxs₁ : x ∈ s₁) (hxs₂ : x ∈ s₂),
    (f s₁ hs₁) ⟨x, hxs₁⟩ = (f s₂ hs₂) ⟨x, hxs₂⟩
s : Set X
hs : IsCompact s
⊢ Tendsto (fun i ↦ restrict s (F i)) l (𝓝 (f s ?m.230))

pp: X : Type u_2
Y : Type u_3
inst✝⁴ : TopologicalSpace X
inst✝³ : TopologicalSpace Y
inst✝² : WeaklyLocallyCompactSpace X
inst✝¹ : T2Space Y
ι : Type u_6
l : Filter ι
inst✝ : l.NeBot
F : ι → C(X, Y)
f : (s : Set X) → IsCompact s → C(↑s, Y)
hf : ∀ (s : Set X) (a : IsCompact s), Tendsto (fun i ↦ restrict s (F i)) l (𝓝 (f s a))
h :
  ∀ (s₁ : Set X) (hs₁ : IsCompact s₁) (s₂ : Set X) (hs₂ : IsCompact s₂) (x : X) (hxs₁ : x ∈ s₁) (hxs₂ : x ∈ s₂),
    (f s₁ hs₁) ⟨x, hxs₁⟩ = (f s₂ hs₂) ⟨x, hxs₂⟩
s : Set X
hs : IsCompact s
⊢ s ∈ fun s ↦ ∀ ⦃f : Filter X⦄ [f.NeBot], f ≤ 𝓟 s → ∃ x ∈ s, ClusterPt x f

Tactic:
exact hf s hs

Goal state after:
Module: Mathlib.Topology.Path

Goal state before:
pp: X : Type u_1
inst✝ : TopologicalSpace X
x y z : X
γ₁ : Path x y
γ₂ : Path y z
t : ℝ
ht : t ≤ 1 / 2
⊢ (γ₁.trans γ₂).extend t = γ₁.extend (2 * t)

Tactic:
by
  obtain _ | ht₀ := le_total t 0
  · repeat rw [extend_of_le_zero _ (by linarith)]
  · rwa [extend_apply _ ⟨ht₀, by linarith⟩, trans_apply, dif_pos, extend_apply]

Goal state after:
Module: Mathlib.Topology.Connected.PathConnected

Goal state before:
pp: X : Type u_1
inst✝ : TopologicalSpace X
x y : X
⊢ mk x = mk y ↔ Joined x y

Tactic:
exact Quotient.eq

Goal state after:
Module: Mathlib.Topology.Path

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
x y z : X
ι : Type u_3
γ✝ : Path x y
a b : X
γ : Path a b
t : ℝ
⊢ γ.extend (min t t) = γ.extend t

Tactic:
min_self

Goal state after:
X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
x y z : X
ι : Type u_3
γ✝ : Path x y
a b : X
γ : Path a b
t : ℝ
⊢ γ.extend t = γ.extend t
Module: Mathlib.Topology.Path

Goal state before:
pp: X : Type u_1
inst✝ : TopologicalSpace X
x y : X
γ : Path x y
f : ↑I → ↑I
hfcont : Continuous f
hf₀ : f 0 = 0
hf₁ : f 1 = 1
t : ↑I
h₁ : Continuous (IccExtend ⋯ f)
this : Icc (IccExtend ⋯ f 0) (IccExtend ⋯ f 1) ⊆ IccExtend ⋯ f '' Icc 0 1
⊢ ∃ a, f a = t

Tactic:
rw [IccExtend_left, IccExtend_right, Icc.mk_zero, Icc.mk_one, hf₀, hf₁] at this

Goal state after:
X : Type u_1
inst✝ : TopologicalSpace X
x y : X
γ : Path x y
f : ↑I → ↑I
hfcont : Continuous f
hf₀ : f 0 = 0
hf₁ : f 1 = 1
t : ↑I
h₁ : Continuous (IccExtend ⋯ f)
this : Icc 0 1 ⊆ IccExtend ⋯ f '' Icc 0 1
⊢ ∃ a, f a = t
Module: Mathlib.Analysis.Normed.Group.AddCircle

Goal state before:
pp: p x ε : ℝ
s : Set ℝ
hs : s ⊆ closedBall x (|p| / 2)
⊢ QuotientAddGroup.mk ⁻¹' closedBall (↑x) ε ∩ s = if ε < |p| / 2 then closedBall x ε ∩ s else s

Tactic:
rcases le_or_gt (|p| / 2) ε with hε | hε
  · rcases eq_or_ne p 0 with (rfl | hp)
    · simp only [abs_zero, zero_div] at hε
      simp only [not_lt.mpr hε, coe_real_preimage_closedBall_period_zero, abs_zero, zero_div,
        if_false, inter_eq_right]
      exact hs.trans (closedBall_subset_closedBall <| by simp [hε])
    simp [closedBall_eq_univ_of_half_period_le p hp (↑x) hε, not_lt.mpr hε]
  · suffices ∀ z : ℤ, closedBall (x + z • p) ε ∩ s = if z = 0 then closedBall x ε ∩ s else ∅ by
      simp [-zsmul_eq_mul, coe_real_preimage_closedBall_eq_iUnion,
        iUnion_inter, iUnion_ite, this, hε]
    intro z
    simp only [Real.closedBall_eq_Icc] at hs ⊢
    rcases eq_or_ne z 0 with (rfl | hz)
    · simp
    simp only [hz, zsmul_eq_mul, if_false, eq_empty_iff_forall_notMem]
    rintro y ⟨⟨hy₁, hy₂⟩, hy₀⟩
    obtain ⟨hy₃, hy₄⟩ := hs hy₀
    rcases lt_trichotomy 0 p with (hp | (rfl : 0 = p) | hp)
    · rcases Int.cast_le_neg_one_or_one_le_cast_of_ne_zero ℝ hz with hz' | hz'
      · have : ↑z * p ≤ -p := by nlinarith
        linarith [abs_eq_self.mpr hp.le]
      · have : p ≤ ↑z * p := by nlinarith
        linarith [abs_eq_self.mpr hp.le]
    · simp only [mul_zero, add_zero, abs_zero, zero_div] at hy₁ hy₂ hε
      linarith
    · rcases Int.cast_le_neg_one_or_one_le_cast_of_ne_zero ℝ hz with hz' | hz'
      · have : -p ≤ ↑z * p := by nlinarith
        linarith [abs_eq_neg_self.mpr hp.le]
      · have : ↑z * p ≤ p := by nlinarith
        linarith [abs_eq_neg_self.mpr hp.le]

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

Goal state before:
pp: case inr
x : ℂ
hx : x ≠ 0
this : ‖x‖ ≠ 0
⊢ ↑‖x‖ * cexp (↑x.arg * I) = x

Tactic:
apply Complex.ext

Goal state after:
case inr.a
x : ℂ
hx : x ≠ 0
this : ‖x‖ ≠ 0
⊢ (↑‖x‖ * cexp (↑x.arg * I)).re = x.re

case inr.a
x : ℂ
hx : x ≠ 0
this : ‖x‖ ≠ 0
⊢ (↑‖x‖ * cexp (↑x.arg * I)).im = x.im