l3lab/ntp-mathlib huggingface dataset:
/-- **Triangle inequality** for the norm. -/
@[to_additive norm_add_le "**Triangle inequality** for the norm."]
theorem norm_mul_le' (a b : E) : ‖a * b‖ ≤ ‖a‖ + ‖b‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b✝ b₁ b₂ : E
r r₁ r₂ : ℝ
a b : E
⊢ ‖a * b‖ ≤ ‖a‖ + ‖b‖

Next tactic:
simpa [dist_eq_norm_div] using dist_triangle a 1 b⁻¹
@[to_additive (attr := simp) norm_nonneg]
theorem norm_nonneg' (a : E) : 0 ≤ ‖a‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
a : E
⊢ 0 ≤ ‖a‖

Next tactic:
rw [← dist_one_right]
@[to_additive (attr := simp) norm_nonneg]
theorem norm_nonneg' (a : E) : 0 ≤ ‖a‖ := by
  rw [← dist_one_right]
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
a : E
⊢ 0 ≤ dist a 1

Next tactic:
exact dist_nonneg
@[to_additive (attr := simp) norm_zero]
theorem norm_one' : ‖(1 : E)‖ = 0 := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ ‖1‖ = 0

Next tactic:
rw [← dist_one_right, dist_self]
@[to_additive]
theorem ne_one_of_norm_ne_zero : ‖a‖ ≠ 0 → a ≠ 1 :=
  mt <| by
    

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ a = 1 → ‖a‖ = 0

Next tactic:
rintro rfl
@[to_additive]
theorem ne_one_of_norm_ne_zero : ‖a‖ ≠ 0 → a ≠ 1 :=
  mt <| by
    rintro rfl
    

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ ‖1‖ = 0

Next tactic:
exact norm_one'
@[to_additive (attr := nontriviality) norm_of_subsingleton]
theorem norm_of_subsingleton' [Subsingleton E] (a : E) : ‖a‖ = 0 := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝³ : SeminormedGroup E
inst✝² : SeminormedGroup F
inst✝¹ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
inst✝ : Subsingleton E
a : E
⊢ ‖a‖ = 0

Next tactic:
rw [Subsingleton.elim a 1, norm_one']
@[to_additive zero_lt_one_add_norm_sq]
theorem zero_lt_one_add_norm_sq' (x : E) : 0 < 1 + ‖x‖ ^ 2 := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
x : E
⊢ 0 < 1 + ‖x‖ ^ 2

Next tactic:
positivity
@[to_additive]
theorem norm_div_le (a b : E) : ‖a / b‖ ≤ ‖a‖ + ‖b‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b✝ b₁ b₂ : E
r r₁ r₂ : ℝ
a b : E
⊢ ‖a / b‖ ≤ ‖a‖ + ‖b‖

Next tactic:
simpa [dist_eq_norm_div] using dist_triangle a 1 b
@[to_additive dist_le_norm_add_norm]
theorem dist_le_norm_add_norm' (a b : E) : dist a b ≤ ‖a‖ + ‖b‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b✝ b₁ b₂ : E
r r₁ r₂ : ℝ
a b : E
⊢ dist a b ≤ ‖a‖ + ‖b‖

Next tactic:
rw [dist_eq_norm_div]
@[to_additive dist_le_norm_add_norm]
theorem dist_le_norm_add_norm' (a b : E) : dist a b ≤ ‖a‖ + ‖b‖ := by
  rw [dist_eq_norm_div]
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b✝ b₁ b₂ : E
r r₁ r₂ : ℝ
a b : E
⊢ ‖a / b‖ ≤ ‖a‖ + ‖b‖

Next tactic:
apply norm_div_le
@[to_additive abs_norm_sub_norm_le]
theorem abs_norm_sub_norm_le' (a b : E) : |‖a‖ - ‖b‖| ≤ ‖a / b‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b✝ b₁ b₂ : E
r r₁ r₂ : ℝ
a b : E
⊢ |‖a‖ - ‖b‖| ≤ ‖a / b‖

Next tactic:
simpa [dist_eq_norm_div] using abs_dist_sub_le a b 1
@[to_additive]
theorem norm_le_norm_add_norm_div' (u v : E) : ‖u‖ ≤ ‖v‖ + ‖u / v‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖u‖ ≤ ‖v‖ + ‖u / v‖

Next tactic:
rw [add_comm]
@[to_additive]
theorem norm_le_norm_add_norm_div' (u v : E) : ‖u‖ ≤ ‖v‖ + ‖u / v‖ := by
  rw [add_comm]
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖u‖ ≤ ‖u / v‖ + ‖v‖

Next tactic:
refine' (norm_mul_le' _ _).trans_eq' _
@[to_additive]
theorem norm_le_norm_add_norm_div' (u v : E) : ‖u‖ ≤ ‖v‖ + ‖u / v‖ := by
  rw [add_comm]
  refine' (norm_mul_le' _ _).trans_eq' _
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖u‖ = ‖u / v * v‖

Next tactic:
rw [div_mul_cancel']
@[to_additive]
theorem norm_le_norm_add_norm_div (u v : E) : ‖v‖ ≤ ‖u‖ + ‖u / v‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖v‖ ≤ ‖u‖ + ‖u / v‖

Next tactic:
rw [norm_div_rev]
@[to_additive]
theorem norm_le_norm_add_norm_div (u v : E) : ‖v‖ ≤ ‖u‖ + ‖u / v‖ := by
  rw [norm_div_rev]
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖v‖ ≤ ‖u‖ + ‖v / u‖

Next tactic:
exact norm_le_norm_add_norm_div' v u
@[to_additive]
theorem norm_le_mul_norm_add (u v : E) : ‖u‖ ≤ ‖u * v‖ + ‖v‖ :=
  calc
    ‖u‖ = ‖u * v / v‖ := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v : E
⊢ ‖u‖ = ‖u * v / v‖

Next tactic:
rw [mul_div_cancel'']
@[to_additive ball_eq]
theorem ball_eq' (y : E) (ε : ℝ) : ball y ε = { x | ‖x / y‖ < ε } :=
  Set.ext fun a => by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
y : E
ε : ℝ
a : E
⊢ a ∈ ball y ε ↔ a ∈ {x | ‖x / y‖ < ε}

Next tactic:
simp [dist_eq_norm_div]
@[to_additive]
theorem ball_one_eq (r : ℝ) : ball (1 : E) r = { x | ‖x‖ < r } :=
  Set.ext fun a => by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a✝ a₁ a₂ b b₁ b₂ : E
r✝ r₁ r₂ r : ℝ
a : E
⊢ a ∈ ball 1 r ↔ a ∈ {x | ‖x‖ < r}

Next tactic:
simp
@[to_additive mem_ball_iff_norm]
theorem mem_ball_iff_norm'' : b ∈ ball a r ↔ ‖b / a‖ < r := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ b ∈ ball a r ↔ ‖b / a‖ < r

Next tactic:
rw [mem_ball, dist_eq_norm_div]
@[to_additive mem_ball_iff_norm']
theorem mem_ball_iff_norm''' : b ∈ ball a r ↔ ‖a / b‖ < r := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ b ∈ ball a r ↔ ‖a / b‖ < r

Next tactic:
rw [mem_ball', dist_eq_norm_div]
@[to_additive] -- porting note: `simp` can prove it
theorem mem_ball_one_iff : a ∈ ball (1 : E) r ↔ ‖a‖ < r := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ a ∈ ball 1 r ↔ ‖a‖ < r

Next tactic:
rw [mem_ball, dist_one_right]
@[to_additive mem_closedBall_iff_norm]
theorem mem_closedBall_iff_norm'' : b ∈ closedBall a r ↔ ‖b / a‖ ≤ r := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ b ∈ closedBall a r ↔ ‖b / a‖ ≤ r

Next tactic:
rw [mem_closedBall, dist_eq_norm_div]
@[to_additive] -- porting note: `simp` can prove it
theorem mem_closedBall_one_iff : a ∈ closedBall (1 : E) r ↔ ‖a‖ ≤ r := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ a ∈ closedBall 1 r ↔ ‖a‖ ≤ r

Next tactic:
rw [mem_closedBall, dist_one_right]
@[to_additive mem_closedBall_iff_norm']
theorem mem_closedBall_iff_norm''' : b ∈ closedBall a r ↔ ‖a / b‖ ≤ r := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ b ∈ closedBall a r ↔ ‖a / b‖ ≤ r

Next tactic:
rw [mem_closedBall', dist_eq_norm_div]
@[to_additive norm_le_of_mem_closedBall]
theorem norm_le_of_mem_closedBall' (h : b ∈ closedBall a r) : ‖b‖ ≤ ‖a‖ + r :=
  (norm_le_norm_add_norm_div' _ _).trans <| add_le_add_left (by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
h : b ∈ closedBall a r
⊢ ‖b / a‖ ≤ r

Next tactic:
rwa [← dist_eq_norm_div]
@[to_additive norm_lt_of_mem_ball]
theorem norm_lt_of_mem_ball' (h : b ∈ ball a r) : ‖b‖ < ‖a‖ + r :=
  (norm_le_norm_add_norm_div' _ _).trans_lt <| add_lt_add_left (by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
h : b ∈ ball a r
⊢ ‖b / a‖ < r

Next tactic:
rwa [← dist_eq_norm_div]
@[to_additive]
theorem norm_div_sub_norm_div_le_norm_div (u v w : E) : ‖u / w‖ - ‖v / w‖ ≤ ‖u / v‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
u v w : E
⊢ ‖u / w‖ - ‖v / w‖ ≤ ‖u / v‖

Next tactic:
simpa only [div_div_div_cancel_right'] using norm_sub_norm_le' (u / w) (v / w)
@[to_additive isBounded_iff_forall_norm_le]
theorem isBounded_iff_forall_norm_le' : Bornology.IsBounded s ↔ ∃ C, ∀ x ∈ s, ‖x‖ ≤ C := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ Bornology.IsBounded s ↔ ∃ C, ∀ x ∈ s, ‖x‖ ≤ C

Next tactic:
simpa only [Set.subset_def, mem_closedBall_one_iff] using isBounded_iff_subset_closedBall (1 : E)
@[to_additive exists_pos_norm_le]
theorem Bornology.IsBounded.exists_pos_norm_le' (hs : IsBounded s) : ∃ R > 0, ∀ x ∈ s, ‖x‖ ≤ R :=
  let ⟨R₀, hR₀⟩ := hs.exists_norm_le'
  ⟨max R₀ 1, by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
hs : IsBounded s
R₀ : ℝ
hR₀ : ∀ x ∈ s, ‖x‖ ≤ R₀
⊢ max R₀ 1 > 0

Next tactic:
positivity
@[to_additive (attr := simp 1001) mem_sphere_iff_norm]
-- porting note: increase priority so the left-hand side doesn't reduce
theorem mem_sphere_iff_norm' : b ∈ sphere a r ↔ ‖b / a‖ = r := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ b ∈ sphere a r ↔ ‖b / a‖ = r

Next tactic:
simp [dist_eq_norm_div]
@[to_additive] -- `simp` can prove this
theorem mem_sphere_one_iff_norm : a ∈ sphere (1 : E) r ↔ ‖a‖ = r := by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ a ∈ sphere 1 r ↔ ‖a‖ = r

Next tactic:
simp [dist_eq_norm_div]
@[to_additive]
theorem ne_one_of_mem_sphere (hr : r ≠ 0) (x : sphere (1 : E) r) : (x : E) ≠ 1 :=
  ne_one_of_norm_ne_zero <| by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
hr : r ≠ 0
x : ↑(sphere 1 r)
⊢ ‖↑x‖ ≠ 0

Next tactic:
rwa [norm_eq_of_mem_sphere' x]
@[to_additive]
theorem NormedCommGroup.tendsto_nhds_one {f : α → E} {l : Filter α} :
    Tendsto f l (𝓝 1) ↔ ∀ ε > 0, ∀ᶠ x in l, ‖f x‖ < ε :=
  Metric.tendsto_nhds.trans <| by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : α → E
l : Filter α
⊢ (∀ ε > 0, ∀ᶠ (x : α) in l, dist (f x) 1 < ε) ↔ ∀ ε > 0, ∀ᶠ (x : α) in l, ‖f x‖ < ε

Next tactic:
simp only [dist_one_right]
@[to_additive]
theorem NormedCommGroup.tendsto_nhds_nhds {f : E → F} {x : E} {y : F} :
    Tendsto f (𝓝 x) (𝓝 y) ↔ ∀ ε > 0, ∃ δ > 0, ∀ x', ‖x' / x‖ < δ → ‖f x' / y‖ < ε := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : E → F
x : E
y : F
⊢ Tendsto f (𝓝 x) (𝓝 y) ↔ ∀ ε > 0, ∃ δ > 0, ∀ (x' : E), ‖x' / x‖ < δ → ‖f x' / y‖ < ε

Next tactic:
simp_rw [Metric.tendsto_nhds_nhds, dist_eq_norm_div]
@[to_additive]
theorem NormedCommGroup.cauchySeq_iff [Nonempty α] [SemilatticeSup α] {u : α → E} :
    CauchySeq u ↔ ∀ ε > 0, ∃ N, ∀ m, N ≤ m → ∀ n, N ≤ n → ‖u m / u n‖ < ε := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝⁴ : SeminormedGroup E
inst✝³ : SeminormedGroup F
inst✝² : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
inst✝¹ : Nonempty α
inst✝ : SemilatticeSup α
u : α → E
⊢ CauchySeq u ↔ ∀ ε > 0, ∃ N, ∀ (m : α), N ≤ m → ∀ (n : α), N ≤ n → ‖u m / u n‖ < ε

Next tactic:
simp [Metric.cauchySeq_iff, dist_eq_norm_div]
@[to_additive]
theorem NormedCommGroup.nhds_basis_norm_lt (x : E) :
    (𝓝 x).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { y | ‖y / x‖ < ε } := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
x : E
⊢ HasBasis (𝓝 x) (fun ε => 0 < ε) fun ε => {y | ‖y / x‖ < ε}

Next tactic:
simp_rw [← ball_eq']
@[to_additive]
theorem NormedCommGroup.nhds_basis_norm_lt (x : E) :
    (𝓝 x).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { y | ‖y / x‖ < ε } := by
  simp_rw [← ball_eq']
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
x : E
⊢ HasBasis (𝓝 x) (fun ε => 0 < ε) fun ε => ball x ε

Next tactic:
exact Metric.nhds_basis_ball
@[to_additive]
theorem NormedCommGroup.nhds_one_basis_norm_lt :
    (𝓝 (1 : E)).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { y | ‖y‖ < ε } := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ HasBasis (𝓝 1) (fun ε => 0 < ε) fun ε => {y | ‖y‖ < ε}

Next tactic:
convert NormedCommGroup.nhds_basis_norm_lt (1 : E)
@[to_additive]
theorem NormedCommGroup.nhds_one_basis_norm_lt :
    (𝓝 (1 : E)).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { y | ‖y‖ < ε } := by
  convert NormedCommGroup.nhds_basis_norm_lt (1 : E)
  

Proof state:
case h.e'_5.h.h.e'_2.h.h.e'_3.h.e'_3
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ x✝¹ : ℝ
x✝ : E
⊢ x✝ = x✝ / 1

Next tactic:
simp
@[to_additive]
theorem NormedCommGroup.uniformity_basis_dist :
    (𝓤 E).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { p : E × E | ‖p.fst / p.snd‖ < ε } := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ HasBasis (𝓤 E) (fun ε => 0 < ε) fun ε => {p | ‖p.1 / p.2‖ < ε}

Next tactic:
convert Metric.uniformity_basis_dist (α := E) using 1
@[to_additive]
theorem NormedCommGroup.uniformity_basis_dist :
    (𝓤 E).HasBasis (fun ε : ℝ => 0 < ε) fun ε => { p : E × E | ‖p.fst / p.snd‖ < ε } := by
  convert Metric.uniformity_basis_dist (α := E) using 1
  

Proof state:
case h.e'_5
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
⊢ (fun ε => {p | ‖p.1 / p.2‖ < ε}) = fun ε => {p | dist p.1 p.2 < ε}

Next tactic:
simp [dist_eq_norm_div]
/-- A homomorphism `f` of seminormed groups is Lipschitz, if there exists a constant `C` such that
for all `x`, one has `‖f x‖ ≤ C * ‖x‖`. The analogous condition for a linear map of
(semi)normed spaces is in `Mathlib/Analysis/NormedSpace/OperatorNorm.lean`. -/
@[to_additive "A homomorphism `f` of seminormed groups is Lipschitz, if there exists a constant
`C` such that for all `x`, one has `‖f x‖ ≤ C * ‖x‖`. The analogous condition for a linear map of
(semi)normed spaces is in `Mathlib/Analysis/NormedSpace/OperatorNorm.lean`."]
theorem MonoidHomClass.lipschitz_of_bound [MonoidHomClass 𝓕 E F] (f : 𝓕) (C : ℝ)
    (h : ∀ x, ‖f x‖ ≤ C * ‖x‖) : LipschitzWith (Real.toNNReal C) f :=
  LipschitzWith.of_dist_le' fun x y => by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝³ : SeminormedGroup E
inst✝² : SeminormedGroup F
inst✝¹ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
inst✝ : MonoidHomClass 𝓕 E F
f : 𝓕
C : ℝ
h : ∀ (x : E), ‖f x‖ ≤ C * ‖x‖
x y : E
⊢ dist (f x) (f y) ≤ C * dist x y

Next tactic:
simpa only [dist_eq_norm_div, map_div] using h (x / y)
@[to_additive]
theorem lipschitzOnWith_iff_norm_div_le {f : E → F} {C : ℝ≥0} :
    LipschitzOnWith C f s ↔ ∀ ⦃x⦄, x ∈ s → ∀ ⦃y⦄, y ∈ s → ‖f x / f y‖ ≤ C * ‖x / y‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : E → F
C : ℝ≥0
⊢ LipschitzOnWith C f s ↔ ∀ ⦃x : E⦄, x ∈ s → ∀ ⦃y : E⦄, y ∈ s → ‖f x / f y‖ ≤ ↑C * ‖x / y‖

Next tactic:
simp only [lipschitzOnWith_iff_dist_le_mul, dist_eq_norm_div]
@[to_additive]
theorem LipschitzOnWith.norm_div_le_of_le {f : E → F} {C : ℝ≥0} (h : LipschitzOnWith C f s)
    (ha : a ∈ s) (hb : b ∈ s) (hr : ‖a / b‖ ≤ r) : ‖f a / f b‖ ≤ C * r :=
  (h.norm_div_le ha hb).trans <| by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : E → F
C : ℝ≥0
h : LipschitzOnWith C f s
ha : a ∈ s
hb : b ∈ s
hr : ‖a / b‖ ≤ r
⊢ ↑C * ‖a / b‖ ≤ ↑C * r

Next tactic:
gcongr
@[to_additive]
theorem lipschitzWith_iff_norm_div_le {f : E → F} {C : ℝ≥0} :
    LipschitzWith C f ↔ ∀ x y, ‖f x / f y‖ ≤ C * ‖x / y‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : E → F
C : ℝ≥0
⊢ LipschitzWith C f ↔ ∀ (x y : E), ‖f x / f y‖ ≤ ↑C * ‖x / y‖

Next tactic:
simp only [lipschitzWith_iff_dist_le_mul, dist_eq_norm_div]
@[to_additive]
theorem LipschitzWith.norm_div_le_of_le {f : E → F} {C : ℝ≥0} (h : LipschitzWith C f)
    (hr : ‖a / b‖ ≤ r) : ‖f a / f b‖ ≤ C * r :=
  (h.norm_div_le _ _).trans <| by 

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝² : SeminormedGroup E
inst✝¹ : SeminormedGroup F
inst✝ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
f : E → F
C : ℝ≥0
h : LipschitzWith C f
hr : ‖a / b‖ ≤ r
⊢ ↑C * ‖a / b‖ ≤ ↑C * r

Next tactic:
gcongr
@[to_additive]
theorem HasCompactMulSupport.exists_bound_of_continuous [TopologicalSpace α]
    {f : α → E} (hf : HasCompactMulSupport f) (h'f : Continuous f) : ∃ C, ∀ x, ‖f x‖ ≤ C := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝³ : SeminormedGroup E
inst✝² : SeminormedGroup F
inst✝¹ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
inst✝ : TopologicalSpace α
f : α → E
hf : HasCompactMulSupport f
h'f : Continuous f
⊢ ∃ C, ∀ (x : α), ‖f x‖ ≤ C

Next tactic:
simpa using (hf.isCompact_range h'f).isBounded.exists_norm_le'
@[to_additive]
theorem MonoidHomClass.isometry_iff_norm [MonoidHomClass 𝓕 E F] (f : 𝓕) :
    Isometry f ↔ ∀ x, ‖f x‖ = ‖x‖ := by
  

Proof state:
𝓕 : Type u_1
𝕜 : Type u_2
α : Type u_3
ι : Type u_4
κ : Type u_5
E : Type u_6
F : Type u_7
G : Type u_8
inst✝³ : SeminormedGroup E
inst✝² : SeminormedGroup F
inst✝¹ : SeminormedGroup G
s : Set E
a a₁ a₂ b b₁ b₂ : E
r r₁ r₂ : ℝ
inst✝ : MonoidHomClass 𝓕 E F
f : 𝓕
⊢ Isometry ⇑f ↔ ∀ (x : E), ‖f x‖ = ‖x‖

Next tactic:
simp only [isometry_iff_dist_eq, dist_eq_norm_div, ← map_div]