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

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁸ : NormedAddCommGroup V
inst✝⁷ : InnerProductSpace ℝ V
inst✝⁶ : MetricSpace P
inst✝⁵ : NormedAddTorsor V P
V₂ : Type u_3
P₂ : Type u_4
inst✝⁴ : NormedAddCommGroup V₂
inst✝³ : InnerProductSpace ℝ V₂
inst✝² : MetricSpace P₂
inst✝¹ : NormedAddTorsor V₂ P₂
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
i : Fin (n + 1)
⊢ 0 < s.height i

Tactic:
by
  positivity

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

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁷ : NormedAddCommGroup V
inst✝⁶ : InnerProductSpace ℝ V
inst✝⁵ : MetricSpace P
inst✝⁴ : NormedAddTorsor V P
V₂ : Type u_3
P₂ : Type u_4
inst✝³ : NormedAddCommGroup V₂
inst✝² : InnerProductSpace ℝ V₂
inst✝¹ : MetricSpace P₂
inst✝ : NormedAddTorsor V₂ P₂
f : P →ᵃⁱ[ℝ] P₂
p₁ p₂ p₃ : P
⊢ InnerProductGeometry.angle (f p₁ -ᵥ f p₂) (f p₃ -ᵥ f p₂) = InnerProductGeometry.angle (p₁ -ᵥ p₂) (p₃ -ᵥ p₂)

Tactic:
← AffineIsometry.map_vsub,

Goal state after:
V : Type u_1
P : Type u_2
inst✝⁷ : NormedAddCommGroup V
inst✝⁶ : InnerProductSpace ℝ V
inst✝⁵ : MetricSpace P
inst✝⁴ : NormedAddTorsor V P
V₂ : Type u_3
P₂ : Type u_4
inst✝³ : NormedAddCommGroup V₂
inst✝² : InnerProductSpace ℝ V₂
inst✝¹ : MetricSpace P₂
inst✝ : NormedAddTorsor V₂ P₂
f : P →ᵃⁱ[ℝ] P₂
p₁ p₂ p₃ : P
⊢ InnerProductGeometry.angle (f.linearIsometry (p₁ -ᵥ p₂)) (f.linearIsometry (p₃ -ᵥ p₂)) =
    InnerProductGeometry.angle (p₁ -ᵥ p₂) (p₃ -ᵥ p₂)
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Affine

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 p₄ : P
r : ℝ
hr : 0 < r
hrv : r • (p₄ -ᵥ p₂) = p₃ -ᵥ p₂
⊢ ∠ p₁ p₂ p₃ = ∠ p₁ p₂ p₄

Tactic:
simp only [angle, ← hrv]
  exact InnerProductGeometry.angle_smul_right_of_pos (p₁ -ᵥ p₂) (p₄ -ᵥ p₂) hr

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

Goal state before:
pp: case a.refine_2
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
n : ℕ
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i j : Fin (n + 1)
hij : i ≠ j
r : ℝ
hr : r ≠ 0
h : s.points j -ᵥ s.altitudeFoot j = r • (s.points i -ᵥ s.altitudeFoot i)
hk : ∃ k, k ≠ i ∧ k ≠ j
hs :
  vectorSpan ℝ (Set.range s.points) =
    vectorSpan ℝ (Set.range (s.faceOpposite i).points) ⊔ vectorSpan ℝ (Set.range (s.faceOpposite j).points)
⊢ s.points j -ᵥ s.altitudeFoot j ∈ (vectorSpan ℝ (Set.range s.points))ᗮ

Tactic:
hs,

Goal state after:
case a.refine_2
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
n : ℕ
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i j : Fin (n + 1)
hij : i ≠ j
r : ℝ
hr : r ≠ 0
h : s.points j -ᵥ s.altitudeFoot j = r • (s.points i -ᵥ s.altitudeFoot i)
hk : ∃ k, k ≠ i ∧ k ≠ j
hs :
  vectorSpan ℝ (Set.range s.points) =
    vectorSpan ℝ (Set.range (s.faceOpposite i).points) ⊔ vectorSpan ℝ (Set.range (s.faceOpposite j).points)
⊢ s.points j -ᵥ s.altitudeFoot j ∈
    (vectorSpan ℝ (Set.range (s.faceOpposite i).points) ⊔ vectorSpan ℝ (Set.range (s.faceOpposite j).points))ᗮ
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.Affine

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
p₀ p : P
⊢ ∠ p p₀ p₀ = π / 2

Tactic:
by rw [angle_comm, angle_self_left]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Rotation

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
r₁ r₂ : ℝ
⊢ ⟪r₂ • x, r₁ • (o.rotation ↑(π / 2)) x⟫ = 0

Tactic:
by
  rw [real_inner_comm, inner_smul_rotation_pi_div_two_smul_left]

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

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y : V
hn : x ≠ y
h : ‖x‖ = ‖y‖
⊢ o.oangle (-y) (-x) + o.oangle x (x - y) + o.oangle (y - x) y = ↑π

Tactic:
have hy : y ≠ 0 := by
    rintro rfl
    rw [norm_zero, norm_eq_zero] at h
    exact hn h

Goal state after:
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y : V
hn : x ≠ y
h : ‖x‖ = ‖y‖
hy : y ≠ 0
⊢ o.oangle (-y) (-x) + o.oangle x (x - y) + o.oangle (y - x) y = ↑π
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Basic

Goal state before:
pp: w z : ℂ
⊢ Complex.orientation.oangle w z = ↑((starRingEnd ℂ) w * z).arg

Tactic:
by
  simp [oangle, mul_comm z]

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

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
h : ⟪x, y⟫ = 0
h0 : x = 0 ∨ y ≠ 0
⊢ 0 < angle x (x - y)

Tactic:
rw [← neg_eq_zero, ← inner_neg_right] at h
  rw [← neg_ne_zero] at h0
  rw [sub_eq_add_neg]
  exact angle_add_pos_of_inner_eq_zero h h0

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

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
w x y z : V
h : InnerProductGeometry.angle w x = InnerProductGeometry.angle y z
hs : (o.oangle w x).sign = (o.oangle z y).sign
⊢ o.oangle w x = o.oangle z y

Tactic:
nth_rw 2 [InnerProductGeometry.angle_comm] at h

Goal state after:
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
w x y z : V
h : InnerProductGeometry.angle w x = InnerProductGeometry.angle z y
hs : (o.oangle w x).sign = (o.oangle z y).sign
⊢ o.oangle w x = o.oangle z y
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ : P
h : ∡ p₁ p₂ p₃ = ↑(π / 2)
⊢ (∡ p₃ p₁ p₂).sign = 1

Tactic:
rw [← oangle_rotate_sign, h, Real.Angle.sign_coe_pi_div_two]

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

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : InnerProductGeometry.angle x y = InnerProductGeometry.angle y z
hs' : ¬(o.oangle x y).sign = -(o.oangle y z).sign
h0 : (o.oangle x y).sign = 0 ∨ (o.oangle y z).sign = 0
⊢ InnerProductGeometry.angle y z = 0 ∨ InnerProductGeometry.angle y z = π

Tactic:
rcases h0 with h0 | h0

Goal state after:
case inl
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : InnerProductGeometry.angle x y = InnerProductGeometry.angle y z
hs' : ¬(o.oangle x y).sign = -(o.oangle y z).sign
h0 : (o.oangle x y).sign = 0
⊢ InnerProductGeometry.angle y z = 0 ∨ InnerProductGeometry.angle y z = π

case inr
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : InnerProductGeometry.angle x y = InnerProductGeometry.angle y z
hs' : ¬(o.oangle x y).sign = -(o.oangle y z).sign
h0 : (o.oangle y z).sign = 0
⊢ InnerProductGeometry.angle y z = 0 ∨ InnerProductGeometry.angle y z = π
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Basic

Goal state before:
pp: case neg.inr
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : InnerProductGeometry.angle x y = InnerProductGeometry.angle y z
hs' : ¬(o.oangle x y).sign = -(o.oangle y z).sign
h0 : (o.oangle x y).sign = 0 ∨ (o.oangle y z).sign = 0
h0' : InnerProductGeometry.angle y z = π
⊢ SameRay ℝ x z

Tactic:
· rw [h0'] at he
        obtain ⟨-, r, hr0, rfl⟩ := InnerProductGeometry.angle_eq_pi_iff.1 h0'
        obtain ⟨-, r', hr'0, rfl⟩ := InnerProductGeometry.angle_eq_pi_iff.1 he
        simp_all

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

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
c p₁ p₂ : P
⊢ -⟪c -ᵥ p₂, p₂ -ᵥ p₁⟫ = 0 ↔ ⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ = 0

Tactic:
← inner_neg_right,

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
c p₁ p₂ : P
⊢ ⟪c -ᵥ p₂, -(p₂ -ᵥ p₁)⟫ = 0 ↔ ⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ = 0
Module: Mathlib.Geometry.Euclidean.PerpBisector

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
c p₁ p₂ : P
⊢ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ + -⟪c -ᵥ p₂, p₁ -ᵥ p₂⟫ = 0 ↔ ⟪c -ᵥ midpoint ℝ p₁ p₂, p₂ -ᵥ p₁⟫ = 0

Tactic:
← inner_neg_right,

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
c p₁ p₂ : P
⊢ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ + ⟪c -ᵥ p₂, -(p₁ -ᵥ p₂)⟫ = 0 ↔ ⟪c -ᵥ midpoint ℝ p₁ p₂, p₂ -ᵥ p₁⟫ = 0
Module: Mathlib.Geometry.Euclidean.PerpBisector

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
c p₁ p₂ : P
⊢ c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ = -⟪c -ᵥ p₂, p₂ -ᵥ p₁⟫

Tactic:
← inner_neg_right,

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
c p₁ p₂ : P
⊢ c ∈ perpBisector p₁ p₂ ↔ ⟪c -ᵥ p₁, p₂ -ᵥ p₁⟫ = ⟪c -ᵥ p₂, -(p₂ -ᵥ p₁)⟫
Module: Mathlib.Geometry.Euclidean.SignedDist

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
v : V
p q : P
h : ¬v = 0
⊢ ‖q -ᵥ p‖ • v = ‖v‖ • (q -ᵥ p) ↔ ∃ a, ↑a • v = q -ᵥ p

Tactic:
refine ⟨fun h => ?_, fun ⟨c, h⟩ => ?_⟩

Goal state after:
case neg.refine_1
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
v : V
p q : P
h✝ : ¬v = 0
h : ‖q -ᵥ p‖ • v = ‖v‖ • (q -ᵥ p)
⊢ ∃ a, ↑a • v = q -ᵥ p

case neg.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
v : V
p q : P
h✝ : ¬v = 0
x✝ : ∃ a, ↑a • v = q -ᵥ p
c : ℝ≥0
h : ↑c • v = q -ᵥ p
⊢ ‖q -ᵥ p‖ • v = ‖v‖ • (q -ᵥ p)
Module: Mathlib.Geometry.Euclidean.Sphere.Basic

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : NormedSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Sphere P
p₁ p₂ : P
h : s.IsDiameter p₁ p₂
⊢ (Equiv.pointReflection s.center) p₂ = p₁

Tactic:
by
  rw [← h.midpoint_eq_center, Equiv.pointReflection_midpoint_right]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Sphere.Tangent

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 : Sphere P
as : AffineSubspace ℝ P
p : P
hpar : as ∥ s.orthRadius p
hp : p ∈ s
q : P
hqs : q ∈ s
hqas : q ∈ as
hqo : as ≤ s.orthRadius q
hd : as.direction ≤ (s.orthRadius q).direction
⊢ as = s.orthRadius p ∨ as = s.orthRadius ((Equiv.pointReflection s.center) p)

Tactic:
rw [hpar.direction_eq, direction_orthRadius_le_iff] at hd

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
s : Sphere P
as : AffineSubspace ℝ P
p : P
hpar : as ∥ s.orthRadius p
hp : p ∈ s
q : P
hqs : q ∈ s
hqas : q ∈ as
hqo : as ≤ s.orthRadius q
hd : ∃ r, q -ᵥ s.center = r • (p -ᵥ s.center)
⊢ as = s.orthRadius p ∨ as = s.orthRadius ((Equiv.pointReflection s.center) p)
Module: Mathlib.Geometry.Euclidean.Sphere.OrthRadius

Goal state before:
pp: case inl.inl.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
s : Sphere P
h : dist s.center s.center < s.radius
hs : Nontrivial V
⊢ Metric.sphere s.center s.radius ∩ ↑(s.orthRadius s.center) = ∅ ↔
    Module.finrank ℝ V = 1 ∧ ¬s.center = s.center ∨ Subsingleton V

Tactic:
· simp only [orthRadius_center, top_coe, Set.inter_univ, not_true_eq_false, and_false,
          not_subsingleton_iff_nontrivial.2 hs, or_self, iff_false, ← Set.nonempty_iff_ne_empty]
        obtain ⟨v, hv⟩ := exists_norm_eq V (dist_nonneg.trans_lt h).le
        exact ⟨v +ᵥ s.center, by simp [hv]⟩

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Incenter

Goal state before:
pp: case inr.inr.inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t signs) = ∡ (excenter t signs) (t.points i₁) (t.points i₃)
hs : excenter t signs = excenter t {i₂}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}

Tactic:
hs,

Goal state after:
case inr.inr.inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t {i₂}) = ∡ (excenter t {i₂}) (t.points i₁) (t.points i₃)
hs : excenter t signs = excenter t {i₂}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}
Module: Mathlib.Geometry.Euclidean.Angle.Incenter

Goal state before:
pp: case inr.inr.inr
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t signs) = ∡ (excenter t signs) (t.points i₁) (t.points i₃)
hs : excenter t signs = excenter t {i₃}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}

Tactic:
hs,

Goal state after:
case inr.inr.inr
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t {i₃}) = ∡ (excenter t {i₃}) (t.points i₁) (t.points i₃)
hs : excenter t signs = excenter t {i₃}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}
Module: Mathlib.Geometry.Euclidean.Angle.Incenter

Goal state before:
pp: case inr.inr.inr
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t {i₃}) = ∡ (excenter t {i₃}) (t.points i₁) (t.points i₃)
hs : excenter t signs = excenter t {i₃}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}

Tactic:
oangle_rev (t.points i₃),

Goal state after:
case inr.inr.inr
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t {i₃}) = -∡ (t.points i₃) (t.points i₁) (excenter t {i₃})
hs : excenter t signs = excenter t {i₃}
⊢ excenter t signs = incenter t ∨ excenter t signs = excenter t {i₁}
Module: Mathlib.Geometry.Euclidean.Angle.Incenter

Goal state before:
pp: case inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t signs) = ∡ (excenter t signs) (t.points i₁) (t.points i₃) + ↑π
hs : excenter t signs = incenter t
⊢ excenter t signs = excenter t {i₂} ∨ excenter t signs = excenter t {i₃}

Tactic:
hs,

Goal state after:
case inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (incenter t) = ∡ (incenter t) (t.points i₁) (t.points i₃) + ↑π
hs : excenter t signs = incenter t
⊢ excenter t signs = excenter t {i₂} ∨ excenter t signs = excenter t {i₃}
Module: Mathlib.Geometry.Euclidean.Angle.Incenter

Goal state before:
pp: case inr.inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t signs) = ∡ (excenter t signs) (t.points i₁) (t.points i₃) + ↑π
hs : excenter t signs = excenter t {i₁}
⊢ excenter t signs = excenter t {i₂} ∨ excenter t signs = excenter t {i₃}

Tactic:
hs,

Goal state after:
case inr.inl
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
signs : Finset (Fin 3)
h : ∡ (t.points i₂) (t.points i₁) (excenter t {i₁}) = ∡ (excenter t {i₁}) (t.points i₁) (t.points i₃) + ↑π
hs : excenter t signs = excenter t {i₁}
⊢ excenter t signs = excenter t {i₂} ∨ excenter t signs = excenter t {i₃}
Module: Mathlib.Geometry.Euclidean.Circumcenter

Goal state before:
pp: case h.right
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
s : AffineSubspace ℝ P
inst✝ : s.direction.HasOrthogonalProjection
ps : Set P
hnps : ps.Nonempty
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
⊢ { center := cc₃, radius := cr₃ } = { center := cc₂, radius := cr₂ }

Tactic:
obtain ⟨t₃, cc₃', hcc₃', hcc₃''⟩ :
      ∃ r : ℝ, ∃ p0 ∈ s, cc₃ = r • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ p0 := by
      rwa [mem_affineSpan_insert_iff (orthogonalProjection_mem p)] at hcc₃

Goal state after:
case h.right
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
s : AffineSubspace ℝ P
inst✝ : s.direction.HasOrthogonalProjection
ps : Set P
hnps : ps.Nonempty
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
t₃ : ℝ
cc₃' : P
hcc₃' : cc₃' ∈ s
hcc₃'' : cc₃ = t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc₃'
⊢ { center := cc₃, radius := cr₃ } = { center := cc₂, radius := cr₂ }
Module: Mathlib.Geometry.Euclidean.Angle.Sphere

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 : Sphere P
p q : P
h : ∠ q p s.center = π / 2
hp : p ∈ s
⊢ s.IsTangentAt p line[ℝ, p, q]

Tactic:
by
  have hp_mem := left_mem_affineSpan_pair ℝ p q
  refine ⟨hp, hp_mem, ?_⟩
  have h_ortho : ⟪q -ᵥ p, p -ᵥ s.center⟫ = 0 := by
    rwa [angle, ← inner_eq_zero_iff_angle_eq_pi_div_two, ← neg_vsub_eq_vsub_rev p s.center,
      inner_neg_right, neg_eq_zero] at h
  have hq : q ∈ s.orthRadius p := by
    simp [Sphere.mem_orthRadius_iff_inner_left, h_ortho]
  rw [affineSpan_le]
  have hp : p ∈ s.orthRadius p := by
    simp [Sphere.self_mem_orthRadius]
  simp_rw [Set.insert_subset_iff, Set.singleton_subset_iff]
  exact ⟨hp, hq⟩

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

Goal state before:
pp: case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hpi : angle x y ≠ π
hxy : ¬x = y
h : ‖x‖ - 0 = ⟪x, 0⟫ * (‖x‖⁻¹ - 0⁻¹)
hx0 : ¬x = 0
hy0 : y = 0
⊢ ‖x‖ = ‖y‖

Tactic:
inner_zero_right,

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hpi : angle x y ≠ π
hxy : ¬x = y
h : ‖x‖ - 0 = 0 * (‖x‖⁻¹ - 0⁻¹)
hx0 : ¬x = 0
hy0 : y = 0
⊢ ‖x‖ = ‖y‖