mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Analysis.Complex.Angle

Goal state before:
pp: case refine_2
x y : ℂ
hy : ‖1‖ = 1
θ : ℝ
hθ : θ ∈ Ioc (-π) π
⊢ (Real.cos θ - 1) ^ 2 + Real.sin θ ^ 2 ≤ θ ^ 2

Tactic:
]

Goal state after:
case refine_2
x y : ℂ
hy : ‖1‖ = 1
θ : ℝ
hθ : θ ∈ Ioc (-π) π
⊢ (Real.cos θ - 1) ^ 2 + Real.sin θ ^ 2 ≤ θ ^ 2
Module: Mathlib.Analysis.Complex.Angle

Goal state before:
pp: x y : ℂ
hy : ‖1‖ = 1
θ : ℝ
hθ : θ ∈ Ioc (-π) π
⊢ 2 * (1 - (1 - θ ^ 2 / 2)) = θ ^ 2

Tactic:
by ring

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

Goal state before:
pp: x y : ℂ
hx : ‖x‖ = 1
hy : ‖y‖ = 1
⊢ 2 / π * angle x y ≤ ‖x - y‖

Tactic:
]

Goal state after:
x y : ℂ
hx : ‖x‖ = 1
hy : ‖y‖ = 1
⊢ 2 / π * angle x y ≤ ‖x - y‖
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
⊢ sin (angle x y) = sin (angle x y) * (‖x‖ * ‖y‖) / (‖x‖ * ‖y‖)

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
⊢ sin (angle x y) = sin (angle x y) * (‖x‖ * ‖y‖) / (‖x‖ * ‖y‖)
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: M : ℝ
z w : ℂ
x✝¹ : M ≠ 0
x✝ : 2 * ↑M - z ≠ 0
h : w = z / (2 * ↑M - z)
⊢ z = 2 * ↑M * (z / (2 * ↑M - z)) / (1 + z / (2 * ↑M - z))

Tactic:
]

Goal state after:
M : ℝ
z w : ℂ
x✝¹ : M ≠ 0
x✝ : 2 * ↑M - z ≠ 0
h : w = z / (2 * ↑M - z)
⊢ z = 2 * ↑M * (z / (2 * ↑M - z)) / (1 + z / (2 * ↑M - z))
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: M : ℝ
z w : ℂ
x✝¹ : M ≠ 0
x✝ : 2 * ↑M - z ≠ 0
h : w = z / (2 * ↑M - z)
⊢ z = z

pp: case h
M : ℝ
z w : ℂ
x✝¹ : M ≠ 0
x✝ : 2 * ↑M - z ≠ 0
h : w = z / (2 * ↑M - z)
⊢ ↑M ≠ 0

Tactic:
]

Goal state after:
case h
M : ℝ
z w : ℂ
x✝¹ : M ≠ 0
x✝ : 2 * ↑M - z ≠ 0
h : w = z / (2 * ↑M - z)
⊢ ↑M ≠ 0
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: case hdb
M : ℝ
w : ℂ
hM : 0 < M
hw : ‖w‖ < 1
⊢ ‖1‖ - ‖w‖ ≤ ‖1 + w‖

Tactic:
]

Goal state after:
case hdb
M : ℝ
w : ℂ
hM : 0 < M
hw : ‖w‖ < 1
⊢ ‖1‖ - ‖w‖ ≤ ‖1 + w‖
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : x + y ≠ 0
⊢ √(⟪x, x⟫ * ⟪x + y, x + y⟫ - ⟪x, x + y⟫ * ⟪x, x + y⟫) / (‖x‖ * ‖x + y‖) =
    √(⟪x, x⟫ * ⟪y, y⟫ - ⟪x, y⟫ * ⟪x, y⟫) / (‖x‖ * ‖x + y‖)

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : x + y ≠ 0
⊢ √(⟪x, x⟫ * ⟪x + y, x + y⟫ - ⟪x, x + y⟫ * ⟪x, x + y⟫) / (‖x‖ * ‖x + y‖) =
    √(⟪x, x⟫ * ⟪y, y⟫ - ⟪x, y⟫ * ⟪x, y⟫) / (‖x‖ * ‖x + y‖)
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: M : ℝ
z : ℂ
x✝¹ : 0 < M
x✝ : z.re ≤ M
⊢ ‖z‖ ^ 2 ≤ ‖2 * ↑M - z‖ ^ 2

Tactic:
]

Goal state after:
M : ℝ
z : ℂ
x✝¹ : 0 < M
x✝ : z.re ≤ M
⊢ ‖z‖ ^ 2 ≤ ‖2 * ↑M - z‖ ^ 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) = 1 ↔ ⟪x, y⟫ / (‖x‖ * ‖y‖) = 1

pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) ≤ 1

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) ≤ 1
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
⊢ dist (f z / (2 * ↑M - f z)) 0 ≤ 1 / R * dist z 0

Tactic:
]

Goal state after:
f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
⊢ dist (f z / (2 * ↑M - f z)) 0 ≤ 1 / R * dist z 0
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
⊢ dist (f z / (2 * ↑M - f z)) (f 0 / (2 * ↑M - f 0)) ≤ 1 / R * dist z 0

Tactic:
]

Goal state after:
f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
⊢ dist (f z / (2 * ↑M - f z)) (f 0 / (2 * ↑M - f 0)) ≤ 1 / R * dist z 0
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) = -1 ↔ ⟪x, y⟫ / (‖x‖ * ‖y‖) = -1

pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ -1 ≤ ⟪x, y⟫ / (‖x‖ * ‖y‖)

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ -1 ≤ ⟪x, y⟫ / (‖x‖ * ‖y‖)
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x z : V
left✝ : x ≠ 0
r : ℝ
hr : r < 0
h : angle x (r • x) = π
⊢ π = π

Tactic:
]

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

Goal state before:
pp: case inr.inr
S : Set ℝ
f : ℝ → ℝ
x : ℝ
hf : ConvexOn ℝ S f
hx : x ∈ interior S
hf_ld : derivWithin f (Iio x) x ≤ 0
hf_rd : 0 ≤ derivWithin f (Ioi x) x
y : ℝ
hy : y ∈ S
hyx : y < x
⊢ slope f y x ≤ 0

Tactic:
]

Goal state after:
case inr.inr
S : Set ℝ
f : ℝ → ℝ
x : ℝ
hf : ConvexOn ℝ S f
hx : x ∈ interior S
hf_ld : derivWithin f (Iio x) x ≤ 0
hf_rd : 0 ≤ derivWithin f (Ioi x) x
y : ℝ
hy : y ∈ S
hyx : y < x
⊢ slope f y x ≤ 0
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ⟪x, y⟫ = -(‖x‖ * ‖y‖)
h₁ : ‖x‖ * ‖y‖ ≠ 0
⊢ π = π

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ⟪x, y⟫ = ‖x‖ * ‖y‖
h₁ : ‖x‖ * ‖y‖ ≠ 0
⊢ 0 = 0

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = π
⊢ ‖x‖ ^ 2 - 2 * -(‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = π
⊢ ‖x‖ ^ 2 - 2 * -(‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = 0
⊢ ‖x‖ ^ 2 + 2 * (‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = 0
⊢ ‖x‖ ^ 2 + 2 * (‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2
Module: Mathlib.Analysis.Complex.BorelCaratheodory

Goal state before:
pp: f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hR : 0 < R
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
w : ℂ := f z / (2 * ↑M - f z)
hzR : ‖z‖ < R
hwR : ‖f z / (2 * ↑M - f z)‖ ≤ ‖z‖ / R
h_denom : 2 * ↑M - f z ≠ 0
⊢ ‖2 * ↑M * (f z / (2 * ↑M - f z)) / (1 + f z / (2 * ↑M - f z))‖ = ‖2 * ↑M * w / (1 + w)‖

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = 0
⊢ ‖x‖ ^ 2 - 2 * (‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ - ‖y‖) ^ 2

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = 0
⊢ ‖x‖ ^ 2 - 2 * (‖x‖ * ‖y‖) + ‖y‖ ^ 2 = (‖x‖ - ‖y‖) ^ 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = ‖x‖ + ‖y‖
⊢ ⟪x, y⟫ = -(‖x‖ * ‖y‖)

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = ‖x‖ + ‖y‖
⊢ ⟪x, y⟫ = -(‖x‖ * ‖y‖)
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2
hxy₁ : 0 ≤ ‖x - y‖
hxy₂ : 0 ≤ ‖x‖ + ‖y‖
⊢ ⟪x, y⟫ = -(‖x‖ * ‖y‖)

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2
hxy₁ : 0 ≤ ‖x - y‖
hxy₂ : 0 ≤ ‖x‖ + ‖y‖
⊢ ⟪x, y⟫ = -(‖x‖ * ‖y‖)
Module: Mathlib.Analysis.Complex.Schwarz

Goal state before:
pp: case inr
f : ℂ → ℂ
c z : ℂ
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
hz : ‖z - c‖ < R₁
hR₁ : 0 < R₁
this :
  ∀ {R₁ : ℝ},
    DifferentiableOn ℂ f (ball c R₁) →
      MapsTo f (ball c R₁) (closedBall (f c) R₂) →
        z ∈ ball c R₁ →
          0 < R₁ →
            DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂) →
              ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / R₁) ^ (n + 1)
hd' : ¬(DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂))
⊢ ∀ᶠ (r : ℝ) in 𝓝[<] R₁, ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / r) ^ (n + 1)

Tactic:
]

Goal state after:
case inr
f : ℂ → ℂ
c z : ℂ
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
hz : ‖z - c‖ < R₁
hR₁ : 0 < R₁
this :
  ∀ {R₁ : ℝ},
    DifferentiableOn ℂ f (ball c R₁) →
      MapsTo f (ball c R₁) (closedBall (f c) R₂) →
        z ∈ ball c R₁ →
          0 < R₁ →
            DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂) →
              ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / R₁) ^ (n + 1)
hd' : ¬(DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂))
⊢ ∀ᶠ (r : ℝ) in 𝓝[<] R₁, ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / r) ^ (n + 1)
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ + ‖y‖) ^ 2
hxy₁ : 0 ≤ ‖x - y‖
hxy₂ : 0 ≤ ‖x‖ + ‖y‖
⊢ (‖x‖ ^ 2 + ‖y‖ ^ 2 - (‖x‖ + ‖y‖) ^ 2) / 2 = -(‖x‖ * ‖y‖)

Tactic:
by ring

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

Goal state before:
pp: f : ℂ → ℂ
M R : ℝ
z : ℂ
hM : 0 < M
hf : DifferentiableOn ℂ f (ball 0 R)
hf₁ : Set.MapsTo f (ball 0 R) {z | z.re ≤ M}
hR : 0 < R
hz : z ∈ ball 0 R
hf₂ : f 0 = 0
w : ℂ := f z / (2 * ↑M - f z)
hzR : ‖z‖ < R
hwR : ‖f z / (2 * ↑M - f z)‖ ≤ ‖z‖ / R
h_denom : 2 * ↑M - f z ≠ 0
⊢ 2 * M * ‖w‖ / (1 - ‖w‖) = 2 * M * (‖w‖ / (1 - ‖w‖))

Tactic:
by ring

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
⊢ ⟪x, y⟫ = ‖x‖ * ‖y‖

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
⊢ ⟪x, y⟫ = ‖x‖ * ‖y‖
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
⊢ |‖x‖ - ‖y‖| ^ 2 = (‖x‖ - ‖y‖) ^ 2

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
⊢ |‖x‖ - ‖y‖| ^ 2 = (‖x‖ - ‖y‖) ^ 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
h1 : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ - ‖y‖) ^ 2
⊢ ⟪x, y⟫ = ‖x‖ * ‖y‖

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
h1 : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ - ‖y‖) ^ 2
⊢ ⟪x, y⟫ = ‖x‖ * ‖y‖
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
h : ‖x - y‖ = |‖x‖ - ‖y‖|
h1 : ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = (‖x‖ - ‖y‖) ^ 2
⊢ ((‖x‖ + ‖y‖) ^ 2 - ‖x‖ ^ 2 - ‖y‖ ^ 2) / 2 = ‖x‖ * ‖y‖

Tactic:
by ring

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ‖x‖ ^ 2 + 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 ↔ ⟪x, y⟫ = 0

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ‖x‖ ^ 2 + 2 * ⟪x, y⟫ + ‖y‖ ^ 2 = ‖x‖ ^ 2 - 2 * ⟪x, y⟫ + ‖y‖ ^ 2 ↔ ⟪x, y⟫ = 0
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos 0 ↔ angle x y = 0

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos 0 ↔ angle x y = 0
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos (π / 2) ↔ angle x y = π / 2

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos (π / 2) ↔ angle x y = π / 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos π ↔ angle x y = π

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ cos (angle x y) = cos π ↔ angle x y = π
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ angle x y = 0 ∨ angle x y = π ↔ angle x y = 0 ∨ angle x y = π

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : angle x y = π / 2
⊢ 1 = 1

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : sin (angle x y) = 1
⊢ √(1 - 1 ^ 2) = 0

Tactic:
]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : sin (angle x y) = 1
⊢ √(1 - 1 ^ 2) = 0
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ¬x = 0
⊢ angle x y = angle x y

Tactic:
]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Basic

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ angle x y = angle x y

Tactic:
]

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

Goal state before:
pp: case hz
f : ℂ → ℂ
c z : ℂ
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
hz : ‖z - c‖ < R₁
hR₁ : 0 < R₁
this :
  ∀ {R₁ : ℝ},
    DifferentiableOn ℂ f (ball c R₁) →
      MapsTo f (ball c R₁) (closedBall (f c) R₂) →
        z ∈ ball c R₁ →
          0 < R₁ →
            DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂) →
              ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / R₁) ^ (n + 1)
hd' : ¬(DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂))
r : ℝ
hzr : ‖z - c‖ < r
hrR₁ : r < R₁
⊢ ‖z - c‖ < r

Tactic:
]

Goal state after:
case hz
f : ℂ → ℂ
c z : ℂ
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
hz : ‖z - c‖ < R₁
hR₁ : 0 < R₁
this :
  ∀ {R₁ : ℝ},
    DifferentiableOn ℂ f (ball c R₁) →
      MapsTo f (ball c R₁) (closedBall (f c) R₂) →
        z ∈ ball c R₁ →
          0 < R₁ →
            DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂) →
              ‖f z - f c‖ ≤ R₂ * (‖z - c‖ / R₁) ^ (n + 1)
hd' : ¬(DifferentiableOn ℂ f (closedBall c R₁) ∧ MapsTo f (closedBall c R₁) (closedBall (f c) R₂))
r : ℝ
hzr : ‖z - c‖ < r
hrR₁ : r < R₁
⊢ ‖z - c‖ < r
Module: Mathlib.Analysis.Complex.Schwarz

Goal state before:
pp: case ho.refine_2
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
w : ℂ
hw : w - c ≠ 0
⊢ (fun x ↦ ((x - c) ^ (n + 1))⁻¹ * (x - c) ^ n) w = (fun z ↦ (z - c)⁻¹) w

Tactic:
]

Goal state after:
case ho.refine_2
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
w : ℂ
hw : w - c ≠ 0
⊢ (fun x ↦ ((x - c) ^ (n + 1))⁻¹ * (x - c) ^ n) w = (fun z ↦ (z - c)⁻¹) w
Module: Mathlib.Analysis.Complex.CoveringMap

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹ : NontriviallyNormedField 𝕜
inst✝ : ProperSpace 𝕜
n : ℕ
hn : ↑n ≠ 0
surj : Function.Surjective fun x ↦ x ^ n
⊢ IsQuotientCoveringMap (fun x ↦ x ^ n) ↥(rootsOfUnity n 𝕜)

Tactic:
]

Goal state after:
𝕜 : Type u_1
inst✝¹ : NontriviallyNormedField 𝕜
inst✝ : ProperSpace 𝕜
n : ℕ
hn : ↑n ≠ 0
surj : Function.Surjective fun x ↦ x ^ n
⊢ IsQuotientCoveringMap (fun x ↦ x ^ n) ↥(rootsOfUnity n 𝕜)
Module: Mathlib.Analysis.Complex.Schwarz

Goal state before:
pp: case inr.refine_1
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
hdg' : DifferentiableOn ℂ g' (closedBall c R₁)
⊢ ∀ z ∈ sphere c R₁, ‖g' z‖ ≤ R₂ / R₁ ^ (n + 1)

Tactic:
]

Goal state after:
case inr.refine_1
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
hdg' : DifferentiableOn ℂ g' (closedBall c R₁)
⊢ ∀ z ∈ sphere c R₁, ‖g' z‖ ≤ R₂ / R₁ ^ (n + 1)
Module: Mathlib.Analysis.Normed.Module.Ball.Action

Goal state before:
pp: 𝕜 : Type u_1
𝕜' : Type u_2
E : Type u_3
inst✝⁴ : NormedField 𝕜
inst✝³ : NormedField 𝕜'
inst✝² : SeminormedAddCommGroup E
inst✝¹ : NormedSpace 𝕜 E
inst✝ : NormedSpace 𝕜' E
r : ℝ
c : ↑(sphere 0 1)
x : ↑(sphere 0 r)
⊢ r = r

Tactic:
]

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

Goal state before:
pp: case inr.refine_1
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
hdg' : DifferentiableOn ℂ g' (closedBall c R₁)
w : ℂ
hw : ‖w - c‖ = R₁
hwc : w ≠ c
hfw : ‖f w - f c‖ ≤ R₂
⊢ ‖g' w‖ ≤ R₂ / R₁ ^ (n + 1)

Tactic:
]

Goal state after:
case inr.refine_1
f : ℂ → ℂ
c z : ℂ
R₂ : ℝ
n : ℕ
hn : (fun x ↦ f x - f c) =o[𝓝 c] fun w ↦ (w - c) ^ n
R₁ : ℝ
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hd : DifferentiableOn ℂ f (closedBall c R₁)
h_maps : MapsTo f (closedBall c R₁) (closedBall (f c) R₂)
hne : z ≠ c
g : ℂ → ℂ := fun w ↦ ((w - c) ^ (n + 1))⁻¹ * (f w - f c)
g' : ℂ → ℂ := update g c ((𝓝[≠] c).limUnder g)
hdg' : DifferentiableOn ℂ g' (closedBall c R₁)
w : ℂ
hw : ‖w - c‖ = R₁
hwc : w ≠ c
hfw : ‖f w - f c‖ ≤ R₂
⊢ ‖g' w‖ ≤ R₂ / R₁ ^ (n + 1)
Module: Mathlib.Analysis.Complex.CoveringMap

Goal state before:
pp: case inr
𝕜 : Type u_1
inst✝¹ : NontriviallyNormedField 𝕜
inst✝ : ProperSpace 𝕜
n : ℕ
hn : ↑(-↑n) ≠ 0
surj : Function.Surjective fun x ↦ x ^ (-↑n)
⊢ IsQuotientCoveringMap (fun x ↦ x ^ (-↑n)) ↥(powMonoidHom n).ker

Tactic:
]

Goal state after:
case inr
𝕜 : Type u_1
inst✝¹ : NontriviallyNormedField 𝕜
inst✝ : ProperSpace 𝕜
n : ℕ
hn : ↑(-↑n) ≠ 0
surj : Function.Surjective fun x ↦ x ^ (-↑n)
⊢ IsQuotientCoveringMap (fun x ↦ x ^ (-↑n)) ↥(powMonoidHom n).ker
Module: Mathlib.Analysis.Complex.BranchLogRoot

Goal state before:
pp: X : Type u_1
inst✝¹ : TopologicalSpace X
inst✝ : LocallyPathConnectedSpace X
U : Set X
hUc : IsSimplyConnected U
hUo : IsOpen U
g✝ : X → ℂ
hgc : ContinuousOn g✝ U
hU₀ : 0 ∉ g✝ '' U
this✝ : SimplyConnectedSpace ↑U
this : LocallyPathConnectedSpace ↑U
x₀ : { x // x ∈ U }
hx₀ : g✝ ↑x₀ ≠ 0
f : C(↑U, ℂ)
hf : cexp ∘ ⇑f = ⇑{ toFun := U.domRestrict g✝, continuous_toFun := ⋯ }
g : X → ℂ
hg : ∀ (z : ↑U), g ↑z = f z
⊢ Continuous (U.domRestrict g)

Tactic:
]

Goal state after:
X : Type u_1
inst✝¹ : TopologicalSpace X
inst✝ : LocallyPathConnectedSpace X
U : Set X
hUc : IsSimplyConnected U
hUo : IsOpen U
g✝ : X → ℂ
hgc : ContinuousOn g✝ U
hU₀ : 0 ∉ g✝ '' U
this✝ : SimplyConnectedSpace ↑U
this : LocallyPathConnectedSpace ↑U
x₀ : { x // x ∈ U }
hx₀ : g✝ ↑x₀ ≠ 0
f : C(↑U, ℂ)
hf : cexp ∘ ⇑f = ⇑{ toFun := U.domRestrict g✝, continuous_toFun := ⋯ }
g : X → ℂ
hg : ∀ (z : ↑U), g ↑z = f z
⊢ Continuous (U.domRestrict g)
Module: Mathlib.Analysis.Complex.Schwarz

Goal state before:
pp: E : Type u_1
F : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℂ E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℂ F
f : E → F
c z : E
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f ((lineMap c z) 0)) =o[𝓝 ((lineMap c z) 0)] fun w ↦ ‖w - (lineMap c z) 0‖ ^ n
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hR₂ : 0 ≤ R₂
hfne : f z ≠ f c
hne : z ≠ c
g : StrongDual ℂ F
hg : ‖g‖ = 1
hgf : g (f z - f c) = ↑‖f z - f c‖
h : ℂ → ℂ := ⇑g ∘ f ∘ ⇑(lineMap c z)
hmaps_line : MapsTo (⇑(lineMap c z)) (ball 0 (R₁ / dist z c)) (ball c R₁)
hmaps : MapsTo h (ball 0 (R₁ / dist z c)) (closedBall (h 0) R₂)
hdiff : DifferentiableOn ℂ h (ball 0 (R₁ / dist z c))
⊢ (fun x ↦ f ((lineMap c z) x) - f ((lineMap c z) 0)) =o[𝓝 0] fun w ↦ w ^ n

Tactic:
]

Goal state after:
E : Type u_1
F : Type u_2
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace ℂ E
inst✝¹ : NormedAddCommGroup F
inst✝ : NormedSpace ℂ F
f : E → F
c z : E
R₁ R₂ : ℝ
n : ℕ
hd : DifferentiableOn ℂ f (ball c R₁)
h_maps : MapsTo f (ball c R₁) (closedBall (f c) R₂)
hn : (fun x ↦ f x - f ((lineMap c z) 0)) =o[𝓝 ((lineMap c z) 0)] fun w ↦ ‖w - (lineMap c z) 0‖ ^ n
hz : z ∈ ball c R₁
hR₁ : 0 < R₁
hR₂ : 0 ≤ R₂
hfne : f z ≠ f c
hne : z ≠ c
g : StrongDual ℂ F
hg : ‖g‖ = 1
hgf : g (f z - f c) = ↑‖f z - f c‖
h : ℂ → ℂ := ⇑g ∘ f ∘ ⇑(lineMap c z)
hmaps_line : MapsTo (⇑(lineMap c z)) (ball 0 (R₁ / dist z c)) (ball c R₁)
hmaps : MapsTo h (ball 0 (R₁ / dist z c)) (closedBall (h 0) R₂)
hdiff : DifferentiableOn ℂ h (ball 0 (R₁ / dist z c))
⊢ (fun x ↦ f ((lineMap c z) x) - f ((lineMap c z) 0)) =o[𝓝 0] fun w ↦ w ^ n