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

Goal state before:
pp: case e'_2.e'_6
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
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
S : AffineSubspace ℝ P := affineSpan ℝ (Set.range t.points)
hS : S = affineSpan ℝ (Set.range t.points)
t' : Triangle ℝ ↥S := Simplex.restrict t S ⋯
hf2 : Fact (finrank ℝ ↥S.direction = 2)
this : Oriented ℝ (↥S.direction) (Fin 2)
⊢ Real.sin (∠ (t.points i₁) (t.points i₂) (t.points i₃)) = |(∡ (t'.points i₁) (t'.points i₂) (t'.points i₃)).sin|

pp: case e'_3
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
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
S : AffineSubspace ℝ P := affineSpan ℝ (Set.range t.points)
hS : S = affineSpan ℝ (Set.range t.points)
t' : Triangle ℝ ↥S := Simplex.restrict t S ⋯
hf2 : Fact (finrank ℝ ↥S.direction = 2)
this : Oriented ℝ (↥S.direction) (Fin 2)
⊢ Simplex.circumradius t = Simplex.circumradius t'

Tactic:
· rw [← Real.Angle.sin_toReal,
      Real.abs_sin_eq_sin_abs_of_abs_le_pi (Real.Angle.abs_toReal_le_pi _),
      ← angle_eq_abs_oangle_toReal (t'.independent.injective.ne h₁₂)
        (t'.independent.injective.ne h₂₃.symm)]
    congr

Goal state after:
case e'_3
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
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
S : AffineSubspace ℝ P := affineSpan ℝ (Set.range t.points)
hS : S = affineSpan ℝ (Set.range t.points)
t' : Triangle ℝ ↥S := Simplex.restrict t S ⋯
hf2 : Fact (finrank ℝ ↥S.direction = 2)
this : Oriented ℝ (↥S.direction) (Fin 2)
⊢ Simplex.circumradius t = Simplex.circumradius t'
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
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
⊢ dist (t.points i₁) (t.points i₃) / Real.sin (∠ (t.points i₁) (t.points i₂) (t.points i₃)) = 2 * Simplex.circumradius t

Tactic:
rw [← t.dist_div_sin_angle_div_two_eq_circumradius h₁₂ h₁₃ h₂₃]

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
t : Triangle ℝ P
i₁ i₂ i₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
⊢ dist (t.points i₁) (t.points i₃) / Real.sin (∠ (t.points i₁) (t.points i₂) (t.points i₃)) =
    2 * (dist (t.points i₁) (t.points i₃) / Real.sin (∠ (t.points i₁) (t.points i₂) (t.points i₃)) / 2)
Module: Mathlib.Geometry.Euclidean.Incenter

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁵ : NormedAddCommGroup V
inst✝⁴ : InnerProductSpace ℝ V
inst✝³ : MetricSpace P
inst✝² : NormedAddTorsor V P
m n : ℕ
inst✝¹ : NeZero m
inst✝ : NeZero n
s : Simplex ℝ P n
e : Fin (n + 1) ≃ Fin (m + 1)
signs : Finset (Fin (m + 1))
i : Fin (m + 1)
⊢ (Finset.affineCombination ℝ Finset.univ (s.reindex e).points)
      (s.touchpointWeights (Finset.map e.symm.toEmbedding signs) (e.symm i) ∘ ⇑e.symm) =
    (Finset.affineCombination ℝ Finset.univ s.points)
      (s.touchpointWeights (Finset.map e.symm.toEmbedding signs) (e.symm i))

Tactic:
reindex

Goal state after:
V : Type u_1
P : Type u_2
inst✝⁵ : NormedAddCommGroup V
inst✝⁴ : InnerProductSpace ℝ V
inst✝³ : MetricSpace P
inst✝² : NormedAddTorsor V P
m n : ℕ
inst✝¹ : NeZero m
inst✝ : NeZero n
s : Simplex ℝ P n
e : Fin (n + 1) ≃ Fin (m + 1)
signs : Finset (Fin (m + 1))
i : Fin (m + 1)
⊢ (Finset.affineCombination ℝ Finset.univ { points := s.points ∘ ⇑e.symm, independent := ⋯ }.points)
      (s.touchpointWeights (Finset.map e.symm.toEmbedding signs) (e.symm i) ∘ ⇑e.symm) =
    (Finset.affineCombination ℝ Finset.univ s.points)
      (s.touchpointWeights (Finset.map e.symm.toEmbedding signs) (e.symm i))
Module: Mathlib.Geometry.Euclidean.Circumcenter

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
n : ℕ
s : Simplex ℝ P n
p p₁ p₂ : P
r : ℝ
h₁ : ∀ (i : Fin (n + 1)), dist (s.points i) p₁ = r
h₂ : ∀ (i : Fin (n + 1)), dist (s.points i) p₂ = r
span_s : AffineSubspace ℝ P := affineSpan ℝ (Set.range s.points)
h₁' : ↑(s.orthogonalProjectionSpan p₁) = s.circumcenter
h₂' : ↑(s.orthogonalProjectionSpan p₂) = s.circumcenter
r₁ r₂ : ℝ
hp₁o : ↑(s.orthogonalProjectionSpan p₁) ∈ affineSpan ℝ (Set.range s.points)
hp₁ : p₁ = r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
hp₂o : ↑(s.orthogonalProjectionSpan p₂) ∈ affineSpan ℝ (Set.range s.points)
hp₂ : p₂ = r₂ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
h : s.points 0 ∈ span_s
hd₁ :
  dist (r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter) s.circumcenter *
      dist (r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter)
        s.circumcenter =
    dist p₂ s.circumcenter * dist p₂ s.circumcenter
hd₂ : dist p₂ s.circumcenter * dist p₂ s.circumcenter = r * r - s.circumradius * s.circumradius
⊢ p₁ = p₂ ∨ p₁ = (reflection (affineSpan ℝ (Set.range s.points))) p₂

Tactic:
hp₂,

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
n : ℕ
s : Simplex ℝ P n
p p₁ p₂ : P
r : ℝ
h₁ : ∀ (i : Fin (n + 1)), dist (s.points i) p₁ = r
h₂ : ∀ (i : Fin (n + 1)), dist (s.points i) p₂ = r
span_s : AffineSubspace ℝ P := affineSpan ℝ (Set.range s.points)
h₁' : ↑(s.orthogonalProjectionSpan p₁) = s.circumcenter
h₂' : ↑(s.orthogonalProjectionSpan p₂) = s.circumcenter
r₁ r₂ : ℝ
hp₁o : ↑(s.orthogonalProjectionSpan p₁) ∈ affineSpan ℝ (Set.range s.points)
hp₁ : p₁ = r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
hp₂o : ↑(s.orthogonalProjectionSpan p₂) ∈ affineSpan ℝ (Set.range s.points)
hp₂ : p₂ = r₂ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
h : s.points 0 ∈ span_s
hd₁ :
  dist (r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter) s.circumcenter *
      dist (r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter)
        s.circumcenter =
    dist (r₂ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter)
        s.circumcenter *
      dist (r₂ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter)
        s.circumcenter
hd₂ : dist p₂ s.circumcenter * dist p₂ s.circumcenter = r * r - s.circumradius * s.circumradius
⊢ p₁ = p₂ ∨ p₁ = (reflection (affineSpan ℝ (Set.range s.points))) p₂
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 : ¬Collinear ℝ {a, b, c}
ha₁ : ∠ a b c = ∠ a' b' c'
hd : dist b c = dist b' c'
ha₂ : ∠ b c a = ∠ b' c' a'
h' : ¬Collinear ℝ {a', b', c'}
ha₃' : ∠ c' a' b' + ∠ a' b' c' + ∠ b' c' a' = Real.pi
ha₃ : ∠ c a b = ∠ c' a' b'
⊢ ![a, b, c] ≅ ![a', b', c']

Tactic:
have h_bac : ¬Collinear ℝ {b, a, c} := by simpa [Set.insert_comm] using h

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 : ¬Collinear ℝ {a, b, c}
ha₁ : ∠ a b c = ∠ a' b' c'
hd : dist b c = dist b' c'
ha₂ : ∠ b c a = ∠ b' c' a'
h' : ¬Collinear ℝ {a', b', c'}
ha₃' : ∠ c' a' b' + ∠ a' b' c' + ∠ b' c' a' = Real.pi
ha₃ : ∠ c a b = ∠ c' a' b'
h_bac : ¬Collinear ℝ {b, a, c}
⊢ ![a, b, c] ≅ ![a', b', c']
Module: Mathlib.Geometry.Euclidean.Inversion.ImageHyperplane

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 x y : P
R : ℝ
hR : R ≠ 0
hx : x ≠ c
hy : y ≠ c
⊢ inversion c R x ∈ perpBisector c (inversion c R y) ↔ dist x y = dist y c

Tactic:
rw [mem_perpBisector_iff_dist_eq, dist_inversion_inversion hx hy, dist_inversion_center]
  simp [field, eq_comm, ↓hx, ↓hy]

Goal state after:
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
m n : ℕ
s : Simplex ℝ P n
e : Fin (n + 1) ≃ Fin (m + 1)
⊢ (↑(m + 1) / ↑(m - 1)) •
        ((affineCombination ℝ univ (s.reindex e).points) (centroidWeights ℝ univ) -ᵥ s.circumcenter) +ᵥ
      s.circumcenter =
    (↑(n + 1) / ↑(n - 1)) • ((affineCombination ℝ univ s.points) (centroidWeights ℝ univ) -ᵥ s.circumcenter) +ᵥ
      s.circumcenter

Tactic:
reindex

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
m n : ℕ
s : Simplex ℝ P n
e : Fin (n + 1) ≃ Fin (m + 1)
⊢ (↑(m + 1) / ↑(m - 1)) •
        ((affineCombination ℝ univ (s.points ∘ ⇑e.symm)) (centroidWeights ℝ univ) -ᵥ s.circumcenter) +ᵥ
      s.circumcenter =
    (↑(n + 1) / ↑(n - 1)) • ((affineCombination ℝ univ s.points) (centroidWeights ℝ univ) -ᵥ s.circumcenter) +ᵥ
      s.circumcenter
Module: Mathlib.Geometry.Euclidean.Similarity

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_not_col : ¬Collinear ℝ {a, b, c}
h₁ : ∠ a b c = ∠ a' b' c'
h₂ : ∠ b c a = ∠ b' c' a'
hne_pi_div_two : ∠ a b c ≠ Real.pi / 2 ∨ ∠ b c a ≠ Real.pi / 2
not_all_eq : a' ≠ b' ∨ b' ≠ c' ∨ a' ≠ c'
h_not_col' : ¬Collinear ℝ {a', b', c'}
h_pos1 : 0 < dist a b
h_pos1' : 0 < dist a' b'
⊢ ![a, b, c] ∼ ![a', b', c']

Tactic:
have h_pos2 : 0 < dist b c := by simp [dist_pos, ne₂₃_of_not_collinear h_not_col]

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_not_col : ¬Collinear ℝ {a, b, c}
h₁ : ∠ a b c = ∠ a' b' c'
h₂ : ∠ b c a = ∠ b' c' a'
hne_pi_div_two : ∠ a b c ≠ Real.pi / 2 ∨ ∠ b c a ≠ Real.pi / 2
not_all_eq : a' ≠ b' ∨ b' ≠ c' ∨ a' ≠ c'
h_not_col' : ¬Collinear ℝ {a', b', c'}
h_pos1 : 0 < dist a b
h_pos1' : 0 < dist a' b'
h_pos2 : 0 < dist b c
⊢ ![a, b, c] ∼ ![a', b', c']
Module: Mathlib.Geometry.Euclidean.Similarity

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_not_col : ¬Collinear ℝ {a, b, c}
h₁ : ∠ a b c = ∠ a' b' c'
h₂ : ∠ b c a = ∠ b' c' a'
hne_pi_div_two : ∠ a b c ≠ Real.pi / 2 ∨ ∠ b c a ≠ Real.pi / 2
not_all_eq : a' ≠ b' ∨ b' ≠ c' ∨ a' ≠ c'
h_not_col' : ¬Collinear ℝ {a', b', c'}
h_pos1 : 0 < dist a b
h_pos1' : 0 < dist a' b'
h_pos2 : 0 < dist b c
⊢ ![a, b, c] ∼ ![a', b', c']

Tactic:
have h_pos2' : 0 < dist b' c' := by simp [dist_pos, ne₂₃_of_not_collinear h_not_col']

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_not_col : ¬Collinear ℝ {a, b, c}
h₁ : ∠ a b c = ∠ a' b' c'
h₂ : ∠ b c a = ∠ b' c' a'
hne_pi_div_two : ∠ a b c ≠ Real.pi / 2 ∨ ∠ b c a ≠ Real.pi / 2
not_all_eq : a' ≠ b' ∨ b' ≠ c' ∨ a' ≠ c'
h_not_col' : ¬Collinear ℝ {a', b', c'}
h_pos1 : 0 < dist a b
h_pos1' : 0 < dist a' b'
h_pos2 : 0 < dist b c
h_pos2' : 0 < dist b' c'
⊢ ![a, b, c] ∼ ![a', b', c']
Module: Mathlib.Geometry.Euclidean.NinePointCircle

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 : Triangle ℝ P
i : Fin 3
⊢ s.points i -ᵥ Simplex.eulerPoint s i = s.points i -ᵥ midpoint ℝ (Simplex.mongePoint s) (s.points i)

Tactic:
Simplex.points_vsub_eulerPoint,

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 : Triangle ℝ P
i : Fin 3
⊢ ((↑2 - 1) / ↑2) • (s.points i -ᵥ Simplex.mongePoint s) = s.points i -ᵥ midpoint ℝ (Simplex.mongePoint s) (s.points i)
Module: Mathlib.Geometry.Euclidean.NinePointCircle

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 : Triangle ℝ P
i : Fin 3
⊢ s.points i -ᵥ Simplex.eulerPoint s i ∈ (affineSpan ℝ (Set.range (Simplex.faceOpposite s i).points)).directionᗮ

Tactic:
Simplex.points_vsub_eulerPoint,

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 : Triangle ℝ P
i : Fin 3
⊢ ((↑2 - 1) / ↑2) • (s.points i -ᵥ Simplex.mongePoint s) ∈
    (affineSpan ℝ (Set.range (Simplex.faceOpposite s i).points)).directionᗮ
Module: Mathlib.Geometry.Euclidean.Sphere.Power

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}
hapb : p ∈ line[ℝ, a, b]
hcpd : p ∈ line[ℝ, c, d]
q : P
r : ℝ
h' : ∀ p ∈ {a, b, c, d}, dist p q = r
ha : dist a q = dist b q
hb : dist b q = r
hc : dist c q = dist d q
hd : dist d q = r
⊢ |dist b q ^ 2 - dist p q ^ 2| = dist c p * dist d p

Tactic:
hb,

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}
hapb : p ∈ line[ℝ, a, b]
hcpd : p ∈ line[ℝ, c, d]
q : P
r : ℝ
h' : ∀ p ∈ {a, b, c, d}, dist p q = r
ha : dist a q = dist b q
hb : dist b q = r
hc : dist c q = dist d q
hd : dist d q = r
⊢ |r ^ 2 - dist p q ^ 2| = dist c p * dist d p
Module: Mathlib.Geometry.Euclidean.Sphere.Power

Goal state before:
pp: V : Type u_1
inst✝⁵ : NormedAddCommGroup V
inst✝⁴ : InnerProductSpace ℝ V
P : Type u_2
inst✝³ : MetricSpace P
inst✝² : NormedAddTorsor V P
inst✝¹ : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ p₄ p : P
h : dist p₁ p * dist p₂ p = dist p₃ p * dist p₄ p
hp₁p₂ : Sbtw ℝ p₁ p p₂
hp₃p₄ : Sbtw ℝ p₃ p p₄
hn : ¬Collinear ℝ {p₁, p, p₃}
h_angle_eq : ∠ p₁ p p₄ = ∠ p₃ p p₂
hcol_p₁pp₂ : Collinear ℝ {p₁, p, p₂}
hcol_p₃pp₄ : Collinear ℝ {p₃, p, p₄}
⊢ Cospherical {p₁, p₂, p₄, p₃}

Tactic:
have h_notcol_p₁p₂p₃ : ¬ Collinear ℝ ({p₁, p₂, p₃} : Set P) := by
    have : AffineIndependent ℝ ![p₁, p, p₃] := affineIndependent_iff_not_collinear_set.mpr hn
    rw [← affineIndependent_iff_not_collinear_set]
    grind [hp₁p₂.left_ne_right, affineIndependent_of_affineIndependent_collinear_ne,
      AffineIndependent.comm_left, AffineIndependent.comm_right]

Goal state after:
V : Type u_1
inst✝⁵ : NormedAddCommGroup V
inst✝⁴ : InnerProductSpace ℝ V
P : Type u_2
inst✝³ : MetricSpace P
inst✝² : NormedAddTorsor V P
inst✝¹ : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ p₄ p : P
h : dist p₁ p * dist p₂ p = dist p₃ p * dist p₄ p
hp₁p₂ : Sbtw ℝ p₁ p p₂
hp₃p₄ : Sbtw ℝ p₃ p p₄
hn : ¬Collinear ℝ {p₁, p, p₃}
h_angle_eq : ∠ p₁ p p₄ = ∠ p₃ p p₂
hcol_p₁pp₂ : Collinear ℝ {p₁, p, p₂}
hcol_p₃pp₄ : Collinear ℝ {p₃, p, p₄}
h_notcol_p₁p₂p₃ : ¬Collinear ℝ {p₁, p₂, p₃}
⊢ Cospherical {p₁, p₂, p₄, p₃}
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
n : ℕ
s : Simplex ℝ P (n + 2)
e : Fin (n + 3) ≃ Fin (n + 3)
i₁ i₂ : Fin (n + 3)
⊢ mk' ((affineCombination ℝ {i₁, i₂}ᶜ (s.reindex e).points) (centroidWeights ℝ {i₁, i₂}ᶜ))
        (ℝ ∙ (s.points (e.symm i₁) -ᵥ s.points (e.symm i₂)))ᗮ ⊓
      affineSpan ℝ (Set.range s.points) =
    mk' ((affineCombination ℝ {e.symm i₁, e.symm i₂}ᶜ s.points) (centroidWeights ℝ {e.symm i₁, e.symm i₂}ᶜ))
        (ℝ ∙ (s.points (e.symm i₁) -ᵥ s.points (e.symm i₂)))ᗮ ⊓
      affineSpan ℝ (Set.range s.points)

Tactic:
reindex

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
n : ℕ
s : Simplex ℝ P (n + 2)
e : Fin (n + 3) ≃ Fin (n + 3)
i₁ i₂ : Fin (n + 3)
⊢ mk' ((affineCombination ℝ {i₁, i₂}ᶜ (s.points ∘ ⇑e.symm)) (centroidWeights ℝ {i₁, i₂}ᶜ))
        (ℝ ∙ (s.points (e.symm i₁) -ᵥ s.points (e.symm i₂)))ᗮ ⊓
      affineSpan ℝ (Set.range s.points) =
    mk' ((affineCombination ℝ {e.symm i₁, e.symm i₂}ᶜ s.points) (centroidWeights ℝ {e.symm i₁, e.symm i₂}ᶜ))
        (ℝ ∙ (s.points (e.symm i₁) -ᵥ s.points (e.symm i₂)))ᗮ ⊓
      affineSpan ℝ (Set.range s.points)
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

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 p' : P
⊢ Collinear ℝ {p, p', s.secondInter p (p' -ᵥ p)}

Tactic:
rw [Set.pair_comm, Set.insert_comm]

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
p p' : P
⊢ Collinear ℝ {s.secondInter p (p' -ᵥ p), p, p'}
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

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 p' : P
hp : p ∈ s
hp' : dist p' s.center < s.radius
⊢ Sbtw ℝ p p' (s.secondInter p (p' -ᵥ p))

Tactic:
by
  refine ⟨Sphere.wbtw_secondInter hp hp'.le, ?_, ?_⟩
  · rintro rfl
    rw [mem_sphere] at hp
    simp [hp] at hp'
  · rintro h
    rw [h, mem_sphere.1 ((Sphere.secondInter_mem _).2 hp)] at hp'
    exact lt_irrefl _ hp'

Goal state after:
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
t : Triangle ℝ P
⊢ t.orthocenter = 3 • (Finset.centroid ℝ univ t.points -ᵥ circumcenter t) +ᵥ circumcenter t

Tactic:
rw [orthocenter_eq_mongePoint, mongePoint_eq_smul_vsub_vadd_circumcenter]
  simp

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

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
s : Sphere P
n : ℕ
inst✝ : n.AtLeastTwo
sx : Affine.Simplex ℝ P n
i : Fin (n + 1)
hi : sx.points i ∈ s
hsx : ∀ (j : Fin (n + 1)), dist (sx.points j) s.center ≤ s.radius
w : Fin (n + 1) → ℝ
hw : ∑ i, w i = 1
hw01 : ∀ (i : Fin (n + 1)), w i ∈ Set.Ioo 0 1
r : ℝ := (1 - w i)⁻¹
hrpos : 0 < r
⊢ (affineSpan ℝ (Set.range (sx.faceOpposite i).points)).SOppSide (sx.points i)
    (s.secondInter (sx.points i) ((Finset.affineCombination ℝ Finset.univ sx.points) w -ᵥ sx.points i))

Tactic:
let p' : P := AffineMap.lineMap (sx.points i) (Finset.univ.affineCombination ℝ sx.points w) r

Goal state after:
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 : Sphere P
n : ℕ
inst✝ : n.AtLeastTwo
sx : Affine.Simplex ℝ P n
i : Fin (n + 1)
hi : sx.points i ∈ s
hsx : ∀ (j : Fin (n + 1)), dist (sx.points j) s.center ≤ s.radius
w : Fin (n + 1) → ℝ
hw : ∑ i, w i = 1
hw01 : ∀ (i : Fin (n + 1)), w i ∈ Set.Ioo 0 1
r : ℝ := (1 - w i)⁻¹
hrpos : 0 < r
p' : P := (AffineMap.lineMap (sx.points i) ((Finset.affineCombination ℝ Finset.univ sx.points) w)) r
⊢ (affineSpan ℝ (Set.range (sx.faceOpposite i).points)).SOppSide (sx.points i)
    (s.secondInter (sx.points i) ((Finset.affineCombination ℝ Finset.univ sx.points) w -ᵥ sx.points i))
Module: Mathlib.Geometry.Manifold.Algebra.SmoothFunctions

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
E' : Type u_3
inst✝¹² : NormedAddCommGroup E'
inst✝¹¹ : NormedSpace 𝕜 E'
H : Type u_4
inst✝¹⁰ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
H' : Type u_5
inst✝⁹ : TopologicalSpace H'
I' : ModelWithCorners 𝕜 E' H'
N : Type u_6
inst✝⁸ : TopologicalSpace N
inst✝⁷ : ChartedSpace H N
E'' : Type u_7
inst✝⁶ : NormedAddCommGroup E''
inst✝⁵ : NormedSpace 𝕜 E''
H'' : Type u_8
inst✝⁴ : TopologicalSpace H''
I'' : ModelWithCorners 𝕜 E'' H''
N' : Type u_9
inst✝³ : TopologicalSpace N'
inst✝² : ChartedSpace H'' N'
n : ℕ∞ω
V : Type u_10
inst✝¹ : NormedAddCommGroup V
inst✝ : NormedSpace 𝕜 V
c₁ c₂ : C^n⟮I, N; 𝓘(𝕜, 𝕜), 𝕜⟯
f : C^n⟮I, N; 𝓘(𝕜, V), V⟯
⊢ (c₁ + c₂) • f = c₁ • f + c₂ • f

Tactic:
by ext x; exact add_smul (c₁ x) (c₂ x) (f x)

Goal state after:
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
p : Fin 3 → P
hps : Set.range p ⊆ s
hpi : Function.Injective p
ha : AffineIndependent ℝ p
t : Triangle ℝ P
left✝ : t.orthocenter ∉ Set.range t.points
hts : s = insert t.orthocenter (Set.range t.points)
⊢ affineSpan ℝ (insert t.orthocenter (Set.range t.points)) = affineSpan ℝ (Set.range t.points)

Tactic:
affineSpan_insert_eq_affineSpan ℝ t.orthocenter_mem_affineSpan

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 : Set P
p : Fin 3 → P
hps : Set.range p ⊆ s
hpi : Function.Injective p
ha : AffineIndependent ℝ p
t : Triangle ℝ P
left✝ : t.orthocenter ∉ Set.range t.points
hts : s = insert t.orthocenter (Set.range t.points)
⊢ affineSpan ℝ (Set.range t.points) = affineSpan ℝ (Set.range t.points)