mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ Real.cos (angle x y) =
    Real.cos (angle x (x + y)) * Real.cos (angle y (y + x)) - Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))

Tactic:
cos_angle,

Goal state after:
case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) =
    Real.cos (angle x (x + y)) * Real.cos (angle y (y + x)) - Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) =
    Real.cos (angle x (x + y)) * Real.cos (angle y (y + x)) - Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))

Tactic:
cos_angle,

Goal state after:
case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) =
    ⟪x, x + y⟫ / (‖x‖ * ‖x + y‖) * Real.cos (angle y (y + x)) - Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) =
    ⟪x, x + y⟫ / (‖x‖ * ‖x + y‖) * Real.cos (angle y (y + x)) - Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))

Tactic:
cos_angle,

Goal state after:
case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ ⟪x, y⟫ / (‖x‖ * ‖y‖) =
    ⟪x, x + y⟫ / (‖x‖ * ‖x + y‖) * (⟪y, y + x⟫ / (‖y‖ * ‖y + x‖)) -
      Real.sin (angle x (x + y)) * Real.sin (angle y (y + x))
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ Real.sin (angle x y) =
    Real.sin (angle x (x + y)) * Real.cos (angle y (y + x)) + Real.cos (angle x (x + y)) * Real.sin (angle y (y + x))

Tactic:
cos_angle,

Goal state after:
case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ Real.sin (angle x y) =
    Real.sin (angle x (x + y)) * (⟪y, y + x⟫ / (‖y‖ * ‖y + x‖)) +
      Real.cos (angle x (x + y)) * Real.sin (angle y (y + x))
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ Real.sin (angle x y) =
    Real.sin (angle x (x + y)) * (⟪y, y + x⟫ / (‖y‖ * ‖y + x‖)) +
      Real.cos (angle x (x + y)) * Real.sin (angle y (y + x))

Tactic:
cos_angle,

Goal state after:
case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hy : y ≠ 0
hxy : x ≠ -y
⊢ Real.sin (angle x y) =
    Real.sin (angle x (x + y)) * (⟪y, y + x⟫ / (‖y‖ * ‖y + x‖)) +
      ⟪x, x + y⟫ / (‖x‖ * ‖x + y‖) * Real.sin (angle y (y + x))
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
p₁ p₂ p₃ : P
h : ∠ p₁ p₂ p₃ = ∠ p₁ p₃ p₂
hpi : ∠ p₂ p₁ p₃ ≠ π
⊢ dist p₁ p₂ = dist p₁ p₃

Tactic:
unfold angle at h hpi

Goal state after:
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
p₁ p₂ p₃ : P
h : InnerProductGeometry.angle (p₁ -ᵥ p₂) (p₃ -ᵥ p₂) = InnerProductGeometry.angle (p₁ -ᵥ p₃) (p₂ -ᵥ p₃)
hpi : InnerProductGeometry.angle (p₂ -ᵥ p₁) (p₃ -ᵥ p₁) ≠ π
⊢ dist p₁ p₂ = dist p₁ p₃
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case neg
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c : P
hbc : ¬b = c
⊢ dist a b ^ 2 + dist a c ^ 2 = 2 * (dist a (midpoint ℝ b c) ^ 2 + (dist b c / 2) ^ 2)

Tactic:
let m := midpoint ℝ b c
    have : dist b c ≠ 0 := (dist_pos.mpr hbc).ne'
    have hm := dist_sq_mul_dist_add_dist_sq_mul_dist a b c m (angle_midpoint_eq_pi b c hbc)
    simp only [m, dist_left_midpoint, dist_right_midpoint, Real.norm_two] at hm
    calc
      dist a b ^ 2 + dist a c ^ 2 = 2 / dist b c * (dist a b ^ 2 *
        ((2 : ℝ)⁻¹ * dist b c) + dist a c ^ 2 * (2⁻¹ * dist b c)) := by
        field
      _ = 2 * (dist a (midpoint ℝ b c) ^ 2 + (dist b c / 2) ^ 2) := by
        rw [hm]
        field

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

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
h₁ : ¬x = y
h₂ : ¬x = -y
H1 : ‖x - ⟪y, x⟫ • y‖ ≠ 0
⊢ (1 - ⟪y, x⟫ * ⟪x, y⟫) ^ 2 + ⟪x - ⟪y, x⟫ • y, x - ⟪y, x⟫ • y⟫ * ⟪x, y⟫ ^ 2 = ⟪x - ⟪y, x⟫ • y, x - ⟪y, x⟫ • y⟫

Tactic:
inner_sub_left,

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
h₁ : ¬x = y
h₂ : ¬x = -y
H1 : ‖x - ⟪y, x⟫ • y‖ ≠ 0
⊢ (1 - ⟪y, x⟫ * ⟪x, y⟫) ^ 2 + (⟪x, x - ⟪y, x⟫ • y⟫ - ⟪⟪y, x⟫ • y, x - ⟪y, x⟫ • y⟫) * ⟪x, y⟫ ^ 2 =
    ⟪x, x - ⟪y, x⟫ • y⟫ - ⟪⟪y, x⟫ • y, x - ⟪y, x⟫ • y⟫
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hxy : ¬x - ⟪x, y⟫ • y = 0
H : 1 - ⟪x, y⟫ ^ 2 ≠ 0
⊢ ⟪x - ⟪x, y⟫ • y, x - ⟪x, y⟫ • y⟫ = 1 - ⟪x, y⟫ ^ 2

Tactic:
inner_sub_left,

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hxy : ¬x - ⟪x, y⟫ • y = 0
H : 1 - ⟪x, y⟫ ^ 2 ≠ 0
⊢ ⟪x, x - ⟪x, y⟫ • y⟫ - ⟪⟪x, y⟫ • y, x - ⟪x, y⟫ • y⟫ = 1 - ⟪x, y⟫ ^ 2
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hz : ‖z‖ = 1
H : angle x y + angle y z ≤ π
H1 :
  ⟪x, z⟫ =
    Real.cos (angle x y) * Real.cos (angle y z) +
      Real.sin (angle y z) *
        (Real.sin (angle x y) * ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫)
H3 : ¬ortho y x = 0
H4 : ¬ortho y z = 0
⊢ -1 ≤ ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫

Tactic:
exact neg_one_le_real_inner_of_norm_eq_one
      (norm_normalize_eq_one_iff.mpr H3) (norm_normalize_eq_one_iff.mpr H4)

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

Goal state before:
pp: case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hz : ‖z‖ = 1
H : angle x z ≠ π
H0 : angle x z = angle x y + angle y z
H1 : ¬angle x z = 0
Hxz : Real.sin (angle x z) ≠ 0
H2 : ¬angle x y = 0
H3 : ¬angle y z = 0
H4 : ¬angle x y = π
H5 : ¬angle y z = π
H6 :
  Real.cos (angle x y) * Real.cos (angle y z) - Real.sin (angle x y) * Real.sin (angle y z) =
    Real.cos (angle x y) * Real.cos (angle y z) +
      Real.sin (angle x y) * Real.sin (angle y z) *
        ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫
Hw : Real.sin (angle x y) * Real.sin (angle y z) ≠ 0
H8 : ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫ = -1
H9 : ortho y x ≠ 0
H10 : ortho y z ≠ 0
⊢ Real.sin (angle x z) • y = Real.sin (angle y z) • x + Real.sin (angle x y) • z

Tactic:
have H11 : ‖normalize (ortho y x)‖ = 1 := norm_normalize_eq_one_iff.mpr H9

Goal state after:
case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hz : ‖z‖ = 1
H : angle x z ≠ π
H0 : angle x z = angle x y + angle y z
H1 : ¬angle x z = 0
Hxz : Real.sin (angle x z) ≠ 0
H2 : ¬angle x y = 0
H3 : ¬angle y z = 0
H4 : ¬angle x y = π
H5 : ¬angle y z = π
H6 :
  Real.cos (angle x y) * Real.cos (angle y z) - Real.sin (angle x y) * Real.sin (angle y z) =
    Real.cos (angle x y) * Real.cos (angle y z) +
      Real.sin (angle x y) * Real.sin (angle y z) *
        ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫
Hw : Real.sin (angle x y) * Real.sin (angle y z) ≠ 0
H8 : ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫ = -1
H9 : ortho y x ≠ 0
H10 : ortho y z ≠ 0
H11 : ‖NormedSpace.normalize (ortho y x)‖ = 1
⊢ Real.sin (angle x z) • y = Real.sin (angle y z) • x + Real.sin (angle x y) • z
Module: Mathlib.Geometry.Euclidean.Congruence

Goal state before:
pp: V₁ : Type u_2
V₂ : Type u_3
P₁ : Type u_4
P₂ : Type u_5
inst✝⁷ : NormedAddCommGroup V₁
inst✝⁶ : NormedAddCommGroup V₂
inst✝⁵ : InnerProductSpace ℝ V₁
inst✝⁴ : InnerProductSpace ℝ V₂
inst✝³ : MetricSpace P₁
inst✝² : MetricSpace P₂
inst✝¹ : NormedAddTorsor V₁ P₁
inst✝ : NormedAddTorsor V₂ P₂
a b c : P₁
a' b' c' : P₂
h : ∠ a b c = ∠ a' b' c'
hd₁ : dist a b = dist a' b'
hd₂ : dist b c = dist b' c'
⊢ dist a c = dist a' c'

Tactic:
← sq_eq_sq₀ (by positivity) (by positivity),

Goal state after:
V₁ : Type u_2
V₂ : Type u_3
P₁ : Type u_4
P₂ : Type u_5
inst✝⁷ : NormedAddCommGroup V₁
inst✝⁶ : NormedAddCommGroup V₂
inst✝⁵ : InnerProductSpace ℝ V₁
inst✝⁴ : InnerProductSpace ℝ V₂
inst✝³ : MetricSpace P₁
inst✝² : MetricSpace P₂
inst✝¹ : NormedAddTorsor V₁ P₁
inst✝ : NormedAddTorsor V₂ P₂
a b c : P₁
a' b' c' : P₂
h : ∠ a b c = ∠ a' b' c'
hd₁ : dist a b = dist a' b'
hd₂ : dist b c = dist b' c'
⊢ dist a c ^ 2 = dist a' c' ^ 2
Module: Mathlib.Geometry.Euclidean.MongePoint

Goal state before:
pp: case e_6.pointIndex
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
n : ℕ
s : Simplex ℝ P (n + 2)
a✝ : Fin (n + 2 + 1)
⊢ ↑(n + 2 + 1) / ↑(n + 1) * ((if a✝ ∈ univ then (↑(#univ))⁻¹ else 0) - 0) + 0 = (↑(n + 1))⁻¹

Tactic:
rw [if_pos (mem_univ _), card_fin]

Goal state after:
case e_6.pointIndex
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
n : ℕ
s : Simplex ℝ P (n + 2)
a✝ : Fin (n + 2 + 1)
⊢ ↑(n + 2 + 1) / ↑(n + 1) * ((↑(n + 2 + 1))⁻¹ - 0) + 0 = (↑(n + 1))⁻¹
Module: Mathlib.Geometry.Euclidean.Sphere.Ptolemy

Goal state before:
pp: V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ dist c d = dist c p / dist b p * dist a b

Tactic:
dist_mul_of_eq_angle_of_dist_mul b p a c p d,

Goal state after:
V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ ?r * dist b a = dist c p / dist b p * dist a b

case r
V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ ℝ

case h
V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ ∠ c p d = ∠ b p a

case hab
V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ dist c p = ?r * dist b p

case hcb
V : Type u_1
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
P : Type u_2
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c d p : P
h : Cospherical {a, b, c, d}
hapc : ∠ a p c = π
hbpd : ∠ b p d = π
h' : Cospherical {a, c, b, d}
hmul : dist a p * dist c p = dist b p * dist d p
hbp : dist b p ≠ 0
⊢ dist d p = ?r * dist a p
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

Goal state before:
pp: case refine_2
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Sphere P
p : P
hp : p ∈ s
v : V
p' : P
hp' : ∃ a, a • v = p' -ᵥ p
h : p' ∈ s
⊢ p' = p ∨ p' = s.secondInter p v

Tactic:
rcases hp' with ⟨r, hr⟩

Goal state after:
case refine_2
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Sphere P
p : P
hp : p ∈ s
v : V
p' : P
h : p' ∈ s
r : ℝ
hr : r • v = p' -ᵥ p
⊢ p' = p ∨ p' = s.secondInter p v
Module: Mathlib.Geometry.Group.Growth.LinearLowerBound

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
X : Finset G
n : ℕ
hX₁ : 1 ∈ X
hX : X.Nontrivial
hn : n ≠ 0
hXn : X ^ n = X ^ (n + 1)
hn₁ : ¬n = 1
this :
  ∀ {G : Type u_1} [inst : Group G] [inst_1 : DecidableEq G] {X : Finset G} {n : ℕ},
    1 ∈ X → X.Nontrivial → n ≠ 0 → X ^ n = X ^ (n + 1) → n = 1 → ↑X = ↑(closure ↑X)
d : ℕ
⊢ X ^ (n + d) = X ^ n

Tactic:
induction d with
      | zero => rw [add_zero]
      | succ d hd =>
        rw [pow_add, pow_one] at hXn
        rw [← add_assoc, pow_add, pow_one, hd, ← hXn]

Goal state after:
Module: Mathlib.Geometry.Euclidean.MongePoint

Goal state before:
pp: case right.inr.inr
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
t : Triangle ℝ P
ho : t.orthocenter ∉ Set.range t.points
p : Fin 3 → P
hps : Set.range p ⊆ insert t.orthocenter (Set.range t.points)
hpi : Function.Injective p
i₁ i₂ i₃ j₂ j₃ : Fin 3
left✝² : i₁ ≠ i₂
left✝¹ : i₁ ≠ i₃
left✝ : i₂ ≠ i₃
h₁₂₃ : ∀ (i : Fin 3), i = i₁ ∨ i = i₂ ∨ i = i₃
h₁ : p i₁ = t.orthocenter
hj₂₃ : j₂ ≠ j₃
h₂ : t.points j₂ = p i₂
h₃ : t.points j₃ = p i₃
⊢ dist (t.points j₃) ((reflection (affineSpan ℝ (t.points '' {j₂, j₃}))) (Simplex.circumcenter t)) =
    Simplex.circumradius t

Tactic:
dist_reflection_eq_of_mem _
          (mem_affineSpan ℝ
            (Set.mem_image_of_mem _ (Set.mem_insert_of_mem _ (Set.mem_singleton _))))

Goal state after:
case right.inr.inr
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
t : Triangle ℝ P
ho : t.orthocenter ∉ Set.range t.points
p : Fin 3 → P
hps : Set.range p ⊆ insert t.orthocenter (Set.range t.points)
hpi : Function.Injective p
i₁ i₂ i₃ j₂ j₃ : Fin 3
left✝² : i₁ ≠ i₂
left✝¹ : i₁ ≠ i₃
left✝ : i₂ ≠ i₃
h₁₂₃ : ∀ (i : Fin 3), i = i₁ ∨ i = i₂ ∨ i = i₃
h₁ : p i₁ = t.orthocenter
hj₂₃ : j₂ ≠ j₃
h₂ : t.points j₂ = p i₂
h₃ : t.points j₃ = p i₃
⊢ dist (t.points j₃) (Simplex.circumcenter t) = Simplex.circumradius t
Module: Mathlib.Geometry.Euclidean.MongePoint

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Set P
t : Triangle ℝ P
hto : t.orthocenter ∉ Set.range t.points
hts : s = insert t.orthocenter (Set.range t.points)
t₂ : Triangle ℝ P
ht₂ : Set.range t₂.points ⊆ insert t.orthocenter (Set.range t.points)
ht₂s : Set.range t₂.points ⊆ s
c : P
hc : c ∈ affineSpan ℝ (Set.range t.points)
h : ∀ (i : Fin 3), dist (t₂.points i) c = Simplex.circumradius t
⊢ Set.range t.points ⊆ insert t.orthocenter (Set.range t.points)

Tactic:
exact Set.subset_insert _ _

Goal state after:
Module: Mathlib.Geometry.Manifold.LocalDiffeomorph

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁵ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹⁴ : NormedAddCommGroup E
inst✝¹³ : NormedSpace 𝕜 E
F : Type u_3
inst✝¹² : NormedAddCommGroup F
inst✝¹¹ : NormedSpace 𝕜 F
F' : Type u_4
inst✝¹⁰ : NormedAddCommGroup F'
inst✝⁹ : NormedSpace 𝕜 F'
H₁ : Type u_5
inst✝⁸ : TopologicalSpace H₁
H₂ : Type u_6
inst✝⁷ : TopologicalSpace H₂
H₃ : Type u_7
inst✝⁶ : TopologicalSpace H₃
I : ModelWithCorners 𝕜 E H₁
J : ModelWithCorners 𝕜 F H₂
K : ModelWithCorners 𝕜 F' H₃
M : Type u_8
inst✝⁵ : TopologicalSpace M
inst✝⁴ : ChartedSpace H₁ M
N : Type u_9
inst✝³ : TopologicalSpace N
inst✝² : ChartedSpace H₂ N
P : Type u_10
inst✝¹ : TopologicalSpace P
inst✝ : ChartedSpace H₃ P
n : WithTop ℕ∞
f : M → N
s : Set M
x : M
I' : ?m.25
hf : IsLocalDiffeomorphAt I J n f x
hn : n ≠ 0
⊢ Function.RightInverse ⇑(mfderiv% ↑hf.localInverse.toPartialEquiv (f x)) ⇑(mfderiv% f x)

Tactic:
apply ContinuousLinearMap.rightInverse_of_comp
    rw [← mfderiv_id, ← hf.localInverse_eventuallyEq_right.mfderiv_eq]
    -- We need to rewrite the base point hf.localInverse (f x) = x twice,
    -- in the differentiability hypothesis and for applying the chain rule.
    have hf' : MDifferentiableAt I J f (hf.localInverse (f x)) := by
      rw [hf.localInverse_left_inv hf.localInverse_mem_target]
      exact hf.mdifferentiableAt hn
    rw [mfderiv_comp _ hf' (hf.localInverse_mdifferentiableAt hn),
      hf.localInverse_left_inv hf.localInverse_mem_target]

Goal state after:
Module: Mathlib.Geometry.Manifold.IsManifold.InteriorBoundary

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
H : Type u_3
inst✝³ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝² : TopologicalSpace M
inst✝¹ : ChartedSpace H M
n : WithTop ℕ∞
inst✝ : IsManifold I n M
hn : n ≠ 0
⊢ IsOpen[inst✝²] (ModelWithCorners.interior M)

Tactic:
refine isOpen_iff_forall_mem_open.2 fun x hx ↦ ⟨_, ?_, isOpen_extChartAt_preimage (I := I) x
    isOpen_interior, mem_chart_source H x, isInteriorPoint_iff.1 hx⟩
  exact fun y hy ↦ (I.isInteriorPoint_iff_of_mem_atlas hn (chart_mem_atlas H x) hy.1).2 hy.2

Goal state after:
Module: Mathlib.Topology.VectorBundle.Hom

Goal state before:
pp: 𝕜 : Type u_8
B : Type u_9
F₁ : Type u_10
F₂ : Type u_11
M : Type u_13
inst✝²⁰ : NontriviallyNormedField 𝕜
E₁ : B → Type u_14
inst✝¹⁹ : (x : B) → AddCommGroup (E₁ x)
inst✝¹⁸ : (x : B) → Module 𝕜 (E₁ x)
inst✝¹⁷ : NormedAddCommGroup F₁
inst✝¹⁶ : NormedSpace 𝕜 F₁
inst✝¹⁵ : TopologicalSpace (TotalSpace F₁ E₁)
inst✝¹⁴ : (x : B) → TopologicalSpace (E₁ x)
E₂ : B → Type u_15
inst✝¹³ : (x : B) → AddCommGroup (E₂ x)
inst✝¹² : (x : B) → Module 𝕜 (E₂ x)
inst✝¹¹ : NormedAddCommGroup F₂
inst✝¹⁰ : NormedSpace 𝕜 F₂
inst✝⁹ : TopologicalSpace (TotalSpace F₂ E₂)
inst✝⁸ : (x : B) → TopologicalSpace (E₂ x)
inst✝⁷ : TopologicalSpace B
inst✝⁶ : TopologicalSpace M
inst✝⁵ : FiberBundle F₁ E₁
inst✝⁴ : VectorBundle 𝕜 F₁ E₁
inst✝³ : FiberBundle F₂ E₂
inst✝² : VectorBundle 𝕜 F₂ E₂
b : M → B
v : (x : M) → E₁ (b x)
inst✝¹ : ∀ (x : B), IsTopologicalAddGroup (E₂ x)
inst✝ : ∀ (x : B), ContinuousSMul 𝕜 (E₂ x)
ϕ : (x : M) → E₁ (b x) →L[𝕜] E₂ (b x)
hϕ :
  Continuous[inst✝⁶, ContinuousLinearMap.topologicalSpaceTotalSpace (RingHom.id 𝕜) F₁ E₁ F₂ E₂] fun m ↦
    TotalSpace.mk' (F₁ →L[𝕜] F₂) (b m) (ϕ m)
hv : Continuous[inst✝⁶, inst✝¹⁵] fun m ↦ TotalSpace.mk' F₁ (b m) (v m)
⊢ Continuous[inst✝⁶, inst✝⁹] fun m ↦ TotalSpace.mk' F₂ (b m) ((ϕ m) (v m))

Tactic:
simp only [← continuousOn_univ] at hϕ hv ⊢
  exact hϕ.clm_bundle_apply hv

Goal state after:
Module: Mathlib.Geometry.Manifold.VectorField.LieBracket

Goal state before:
pp: case e_6.hV
𝕜 : Type u_1
inst✝⁵ : NontriviallyNormedField 𝕜
H : Type u_2
inst✝⁴ : TopologicalSpace H
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
s : Set M
x : M
V W V₁ W₁ : (x : M) → TangentSpace I x
hV : V₁ =ᶠ[𝓝[s] x] V
hxV : V₁ x = V x
hW : W₁ =ᶠ[𝓝[s] x] W
hxW : W₁ x = W x
I1 : NormedAddCommGroup (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := ⋯
_I2 : NormedSpace 𝕜 (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := inst✝²
⊢ mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) V₁
      (range ↑I) =ᶠ[𝓝[↑(extChartAt I x).symm ⁻¹' s ∩ range ↑I] ↑(extChartAt I x) x]
    mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) V (range ↑I)

Tactic:
apply nhdsWithin_mono _ inter_subset_left

Goal state after:
case e_6.hV
𝕜 : Type u_1
inst✝⁵ : NontriviallyNormedField 𝕜
H : Type u_2
inst✝⁴ : TopologicalSpace H
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
s : Set M
x : M
V W V₁ W₁ : (x : M) → TangentSpace I x
hV : V₁ =ᶠ[𝓝[s] x] V
hxV : V₁ x = V x
hW : W₁ =ᶠ[𝓝[s] x] W
hxW : W₁ x = W x
I1 : NormedAddCommGroup (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := ⋯
_I2 : NormedSpace 𝕜 (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := inst✝²
⊢ {x_1 |
      (fun x_2 ↦
          mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) V₁ (range ↑I) x_2 =
            mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) V (range ↑I) x_2)
        x_1} ∈
    𝓝[↑(extChartAt I x).symm ⁻¹' s] ↑(extChartAt I x) x
Module: Mathlib.Geometry.Manifold.VectorField.LieBracket

Goal state before:
pp: case e_6.hW
𝕜 : Type u_1
inst✝⁵ : NontriviallyNormedField 𝕜
H : Type u_2
inst✝⁴ : TopologicalSpace H
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
s : Set M
x : M
V W V₁ W₁ : (x : M) → TangentSpace I x
hV : V₁ =ᶠ[𝓝[s] x] V
hxV : V₁ x = V x
hW : W₁ =ᶠ[𝓝[s] x] W
hxW : W₁ x = W x
I1 : NormedAddCommGroup (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := ⋯
_I2 : NormedSpace 𝕜 (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := inst✝²
⊢ mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) W₁
      (range ↑I) =ᶠ[𝓝[↑(extChartAt I x).symm ⁻¹' s ∩ range ↑I] ↑(extChartAt I x) x]
    mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) W (range ↑I)

Tactic:
apply nhdsWithin_mono _ inter_subset_left

Goal state after:
case e_6.hW
𝕜 : Type u_1
inst✝⁵ : NontriviallyNormedField 𝕜
H : Type u_2
inst✝⁴ : TopologicalSpace H
E : Type u_3
inst✝³ : NormedAddCommGroup E
inst✝² : NormedSpace 𝕜 E
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
s : Set M
x : M
V W V₁ W₁ : (x : M) → TangentSpace I x
hV : V₁ =ᶠ[𝓝[s] x] V
hxV : V₁ x = V x
hW : W₁ =ᶠ[𝓝[s] x] W
hxW : W₁ x = W x
I1 : NormedAddCommGroup (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := ⋯
_I2 : NormedSpace 𝕜 (TangentSpace 𝓘(𝕜, E) (↑(extChartAt I x) x)) := inst✝²
⊢ {x_1 |
      (fun x_2 ↦
          mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) W₁ (range ↑I) x_2 =
            mpullbackWithin 𝓘(𝕜, E) I (↑(extChartAt I x).symm) W (range ↑I) x_2)
        x_1} ∈
    𝓝[↑(extChartAt I x).symm ⁻¹' s] ↑(extChartAt I x) x