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

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 p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
⊢ (∡ p₁ p₅ p₂).sign = (∡ p₃ p₅ p₄).sign

Tactic:
by_cases hc₅₁₂ : Collinear ℝ ({p₅, p₁, p₂} : Set P)

Goal state after:
case pos
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 p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : Collinear ℝ {p₅, p₁, p₂}
⊢ (∡ p₁ p₅ p₂).sign = (∡ p₃ p₅ p₄).sign

case neg
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 p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : ¬Collinear ℝ {p₅, p₁, p₂}
⊢ (∡ p₁ p₅ p₂).sign = (∡ p₃ p₅ p₄).sign
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Affine

Goal state before:
pp: case refine_1
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 p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : ¬Collinear ℝ {p₅, p₁, p₂}
s : Set (P × P × P) := (fun x ↦ (↑x.1, p₅, x.2 +ᵥ ↑x.1)) '' Set.univ ×ˢ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0}
hco : IsConnected s
p : P × P × P
hp : p ∈ s
⊢ p.1 ≠ p.2.1

Tactic:
simp_rw [s, Set.mem_image, Set.mem_prod, Set.mem_univ, true_and, Prod.ext_iff] at hp

Goal state after:
case refine_1
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 p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : ¬Collinear ℝ {p₅, p₁, p₂}
s : Set (P × P × P) := (fun x ↦ (↑x.1, p₅, x.2 +ᵥ ↑x.1)) '' Set.univ ×ˢ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0}
hco : IsConnected s
p : P × P × P
hp : ∃ x, x.2 ∈ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0} ∧ ↑x.1 = p.1 ∧ p₅ = p.2.1 ∧ x.2 +ᵥ ↑x.1 = p.2.2
⊢ p.1 ≠ p.2.1
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Affine

Goal state before:
pp: case 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
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : ¬Collinear ℝ {p₅, p₁, p₂}
s : Set (P × P × P) := (fun x ↦ (↑x.1, p₅, x.2 +ᵥ ↑x.1)) '' Set.univ ×ˢ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0}
hco : IsConnected s
p : P × P × P
hp : p ∈ s
⊢ p.2.2 ≠ p.2.1

Tactic:
simp_rw [s, Set.mem_image, Set.mem_prod, Set.mem_univ, true_and, Prod.ext_iff] at hp

Goal state after:
case 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
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ p₄ p₅ : P
hp₁p₂ : p₁ ≠ p₂
hp₃p₄ : p₃ ≠ p₄
hc : Collinear ℝ {p₁, p₂, p₃, p₄}
hr : SameRay ℝ (p₂ -ᵥ p₁) (p₄ -ᵥ p₃)
hc₅₁₂ : ¬Collinear ℝ {p₅, p₁, p₂}
s : Set (P × P × P) := (fun x ↦ (↑x.1, p₅, x.2 +ᵥ ↑x.1)) '' Set.univ ×ˢ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0}
hco : IsConnected s
p : P × P × P
hp : ∃ x, x.2 ∈ {v | SameRay ℝ (p₂ -ᵥ p₁) v ∧ v ≠ 0} ∧ ↑x.1 = p.1 ∧ p₅ = p.2.1 ∧ x.2 +ᵥ ↑x.1 = p.2.2
⊢ p.2.2 ≠ p.2.1
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
p₁ p₂ : P
⊢ perpBisector p₁ p₂ = perpBisector p₂ p₁

Tactic:
ext c; simp only [mem_perpBisector_iff_dist_eq, eq_comm]

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

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
v : V
p₁ p₂ : P
hv : v ≠ 0
r : ℝ
⊢ dist (r • v +ᵥ p₁) p₂ = dist p₁ p₂ ↔ r = 0 ∨ r = -2 * ⟪v, p₁ -ᵥ p₂⟫ / ⟪v, v⟫

Tactic:
by
  conv_lhs =>
    rw [← mul_self_inj_of_nonneg dist_nonneg dist_nonneg, dist_smul_vadd_sq, mul_assoc,
      ← sub_eq_zero, add_sub_assoc, dist_eq_norm_vsub V p₁ p₂, ← real_inner_self_eq_norm_mul_norm,
      sub_self]
  have hvi : ⟪v, v⟫ ≠ 0 := by simpa using hv
  have hd : discrim ⟪v, v⟫ (2 * ⟪v, p₁ -ᵥ p₂⟫) 0 = 2 * ⟪v, p₁ -ᵥ p₂⟫ * (2 * ⟪v, p₁ -ᵥ p₂⟫) := by
    rw [discrim]
    ring
  rw [quadratic_eq_zero_iff hvi hd, neg_add_cancel, zero_div, neg_mul_eq_neg_mul, ←
    mul_sub_right_distrib, sub_eq_add_neg, ← mul_two, mul_assoc, mul_div_assoc, mul_div_mul_left,
    mul_div_assoc]
  simp

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

Goal state before:
pp: case 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
s : AffineSubspace ℝ P
inst✝ : FiniteDimensional ℝ ↥s.direction
hd : finrank ℝ ↥s.direction = 2
c₁ c₂ p₁ p₂ p : P
hc₁s : c₁ ∈ s
hc₂s : c₂ ∈ s
hp₁s : p₁ ∈ s
hp₂s : p₂ ∈ s
hps : p ∈ s
r₁ r₂ : ℝ
hc : c₁ ≠ c₂
hp : p₁ ≠ p₂
hp₁c₁ : dist p₁ c₁ = r₁
hp₂c₁ : dist p₂ c₁ = r₁
hpc₁ : dist p c₁ = r₁
hp₁c₂ : dist p₁ c₂ = r₂
hp₂c₂ : dist p₂ c₂ = r₂
hpc₂ : dist p c₂ = r₂
ho : ⟪c₂ -ᵥ c₁, p₂ -ᵥ p₁⟫ = 0
hop : ⟪c₂ -ᵥ c₁, p -ᵥ p₁⟫ = 0
b : Fin 2 → V := ![c₂ -ᵥ c₁, p₂ -ᵥ p₁]
hb : LinearIndependent ℝ b
⊢ finrank ℝ ↥(Submodule.span ℝ (Set.range b)) = finrank ℝ ↥s.direction

Tactic:
· rw [finrank_span_eq_card hb, Fintype.card_fin, hd]

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

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
inst✝¹ : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p p₁ p₂ p₃ : P
h₂ : p₁ ≠ p₂
h : 2 • ∡ p₂ p₁ p = 2 • ∡ p p₁ p₃
h' : ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = p₁
⊢ dist p ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = dist p ↑((orthogonalProjection line[ℝ, p₁, p₃]) p)

Tactic:
obtain rfl | hp := eq_or_ne p p₁
  · rw [h', dist_self, zero_eq_dist, eq_comm, orthogonalProjection_eq_self_iff]
    exact left_mem_affineSpan_pair _ _ _
  · rw [← h'] at h hp
    have hpm : p ∉ line[ℝ, p₁, p₂] := orthogonalProjection_eq_self_iff.not.1 (Ne.symm hp)
    rw [two_zsmul_oangle_orthogonalProjection_self _ hpm (right_mem_affineSpan_pair _ _ _)
          (h'.symm ▸ h₂.symm), eq_comm, oangle, Real.Angle.two_zsmul_eq_pi_iff, h'] at h
    replace h := (Orientation.eq_zero_or_oangle_eq_iff_inner_eq_zero _).1 (.inr (.inr h))
    congr 1
    rw [h', eq_comm, coe_orthogonalProjection_eq_iff_mem]
    refine ⟨left_mem_affineSpan_pair _ _ _, ?_⟩
    rw [Submodule.mem_orthogonal']
    intro u hu
    rw [direction_affineSpan, mem_vectorSpan_pair] at hu
    rcases hu with ⟨r, rfl⟩
    rw [inner_smul_right, ← inner_neg_neg, inner_neg_left]
    simp [h]

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

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
v : V
hv0 : v ≠ 0
c : P
r : ℝ
hs : ∀ p ∈ s, dist p c = r
hs' : ∀ (i : Fin 3), dist (p i) c = r
f : Fin 3 → ℝ
hf : ∀ (i : Fin 3), p i = f i • v +ᵥ p 0
hf0 : f 0 = 0
hfi : Function.Injective f
hsd : ∀ (i : Fin 3), f i = 0 ∨ f i = -2 * ⟪v, p 0 -ᵥ c⟫ / ⟪v, v⟫
hfn0 : ∀ (i : Fin 3), i ≠ 0 → f i ≠ 0
i : Fin 3
hi : i ≠ 0
hsdi : f i = 0 ∨ f i = -2 * ⟪v, p 0 -ᵥ c⟫ / ⟪v, v⟫
⊢ f i = -2 * ⟪v, p 0 -ᵥ c⟫ / ⟪v, v⟫

Tactic:
simpa [hfn0, hi] using hsdi

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

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
v : V
hv0 : v ≠ 0
c : P
r : ℝ
hs : ∀ p ∈ s, dist p c = r
hs' : ∀ (i : Fin 3), dist (p i) c = r
f : Fin 3 → ℝ
hf : ∀ (i : Fin 3), p i = f i • v +ᵥ p 0
hf0 : f 0 = 0
hfi : Function.Injective f
hsd : ∀ (i : Fin 3), f i = 0 ∨ f i = -2 * ⟪v, p 0 -ᵥ c⟫ / ⟪v, v⟫
hfn0 : ∀ (i : Fin 3), i ≠ 0 → f i ≠ 0
hfn0' : ∀ (i : Fin 3), i ≠ 0 → f i = -2 * ⟪v, p 0 -ᵥ c⟫ / ⟪v, v⟫
⊢ f 1 = f 2

Tactic:
rw [hfn0' 1 (by decide), hfn0' 2 (by decide)]

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

Goal state before:
pp: case refine_2.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
s : Sphere P
as : AffineSubspace ℝ P
hr : s.radius = 0
hm : s.center ∈ as
⊢ s.center ∈ s

Tactic:
center_mem_iff,

Goal state after:
case refine_2.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
s : Sphere P
as : AffineSubspace ℝ P
hr : s.radius = 0
hm : s.center ∈ as
⊢ s.radius = 0
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
p₁ p₂ q : P
as₁ as₂ : AffineSubspace ℝ P
h₁ : s.IsTangentAt p₁ as₁
h₂ : s.IsTangentAt p₂ as₂
hq_mem₁ : q ∈ as₁
hq_mem₂ : q ∈ as₂
⊢ dist q p₁ = dist q p₂

Tactic:
have h1 := dist_sq_eq_of_mem h₁ hq_mem₁
  have h2 := dist_sq_eq_of_mem h₂ hq_mem₂
  rwa [h1, add_left_cancel_iff, sq_eq_sq₀ dist_nonneg dist_nonneg] at h2

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

Goal state before:
pp: case refine_1.refine_2
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
s : Sphere P
as : AffineSubspace ℝ P
inst✝¹ : Nonempty ↥as
inst✝ : as.direction.HasOrthogonalProjection
h : dist s.center ↑((orthogonalProjection as) s.center) = s.radius
p : P
hp : p ∈ as
⊢ p ∈ s.orthRadius ↑((orthogonalProjection as) s.center)

Tactic:
· rw [mem_orthRadius_iff_inner_left]
      exact orthogonalProjection_vsub_mem_direction_orthogonal as s.center _
        (vsub_orthogonalProjection_mem_direction s.center hp)

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

Goal state before:
pp: case refine_2.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
s₁ s₂ : Sphere P
hr : s₁.radius = 0
hc : s₁.center ∈ s₂
⊢ s₁.center ∈ s₁

Tactic:
center_mem_iff,

Goal state after:
case refine_2.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
s₁ s₂ : Sphere P
hr : s₁.radius = 0
hc : s₁.center ∈ s₂
⊢ s₁.radius = 0
Module: Mathlib.Geometry.Euclidean.Sphere.Tangent

Goal state before:
pp: case center
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
inst✝ : Nontrivial V
s₁ s₂ : Sphere P
h : s₁.radius = s₂.radius
h₁ : 0 ≤ s₁.radius
h₂ : 0 ≤ s₂.radius
h0 : s₁.center = s₂.center
⊢ s₁.center = s₂.center

Tactic:
assumption

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

Goal state before:
pp: case radius
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
inst✝ : Nontrivial V
s₁ s₂ : Sphere P
h : s₁.radius = s₂.radius
h₁ : 0 ≤ s₁.radius
h₂ : 0 ≤ s₂.radius
h0 : s₁.center = s₂.center
⊢ s₁.radius = s₂.radius

Tactic:
assumption

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

Goal state before:
pp: case e'_2.e'_5
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i : Fin (n + 1)
⊢ SignType.sign (∑ i_1, s.excenterWeightsUnnorm {i} i_1)⁻¹ = 1

pp: case e'_3
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i : Fin (n + 1)
⊢ -1 = SignType.sign (s.excenterWeightsUnnorm {i} i)

Tactic:
· rw [sign_eq_one_iff, inv_pos]
    exact s.sum_excenterWeightsUnnorm_singleton_pos i

Goal state after:
case e'_3
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i : Fin (n + 1)
⊢ -1 = SignType.sign (s.excenterWeightsUnnorm {i} i)
Module: Mathlib.Geometry.Euclidean.Incenter

Goal state before:
pp: case e'_2.e'_5
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i j : Fin (n + 1)
h : i ≠ j
⊢ SignType.sign (∑ i_1, s.excenterWeightsUnnorm {i} i_1)⁻¹ = 1

pp: case e'_3
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i j : Fin (n + 1)
h : i ≠ j
⊢ 1 = SignType.sign (s.excenterWeightsUnnorm {i} j)

Tactic:
· rw [sign_eq_one_iff, inv_pos]
    exact s.sum_excenterWeightsUnnorm_singleton_pos i

Goal state after:
case e'_3
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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
inst✝ : n.AtLeastTwo
i j : Fin (n + 1)
h : i ≠ j
⊢ 1 = SignType.sign (s.excenterWeightsUnnorm {i} j)
Module: Mathlib.Geometry.Euclidean.Incenter

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i : Fin (n + 1)
⊢ (affineSpan ℝ (Set.range (s.faceOpposite i).points)).SSameSide (s.points i)
      ((Finset.affineCombination ℝ Finset.univ s.points) (s.excenterWeights signs)) ↔
    0 < s.excenterWeights signs i

Tactic:
s.sSameSide_affineSpan_faceOpposite_point_left_iff h.sum_excenterWeights_eq_one

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i : Fin (n + 1)
⊢ 0 < s.excenterWeights signs i ↔ 0 < s.excenterWeights signs i
Module: Mathlib.Geometry.Euclidean.Circumcenter

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
n : ℕ
s : Simplex ℝ P n
f : P →ᵃⁱ[ℝ] P₂
⊢ (s.map f.toAffineMap ⋯).circumcenter = f s.circumcenter

Tactic:
rw [eq_comm]

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
n : ℕ
s : Simplex ℝ P n
f : P →ᵃⁱ[ℝ] P₂
⊢ f s.circumcenter = (s.map f.toAffineMap ⋯).circumcenter
Module: Mathlib.Geometry.Euclidean.Circumcenter

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
n : ℕ
s : Simplex ℝ P n
f : P →ᵃⁱ[ℝ] P₂
⊢ (s.map f.toAffineMap ⋯).circumradius = s.circumradius

Tactic:
rw [eq_comm]

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
n : ℕ
s : Simplex ℝ P n
f : P →ᵃⁱ[ℝ] P₂
⊢ s.circumradius = (s.map f.toAffineMap ⋯).circumradius
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
S : AffineSubspace ℝ P
hS : affineSpan ℝ (Set.range s.points) ≤ S
⊢ ↑(s.restrict S hS).circumcenter = s.circumcenter

Tactic:
rw [eq_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
n : ℕ
s : Simplex ℝ P n
S : AffineSubspace ℝ P
hS : affineSpan ℝ (Set.range s.points) ≤ S
⊢ s.circumcenter = ↑(s.restrict S hS).circumcenter
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
S : AffineSubspace ℝ P
hS : affineSpan ℝ (Set.range s.points) ≤ S
⊢ (s.restrict S hS).circumradius = s.circumradius

Tactic:
rw [eq_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
n : ℕ
s : Simplex ℝ P n
S : AffineSubspace ℝ P
hS : affineSpan ℝ (Set.range s.points) ≤ S
⊢ s.circumradius = (s.restrict S hS).circumradius
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case 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
a b c p x : P
hx : Sbtw ℝ a x c
hxb : SameRay ℝ (x -ᵥ p) (b -ᵥ p)
hb : b ≠ p
hpx : p ≠ x
r : ℝ
hr : 0 < r
hrb : r • (x -ᵥ p) = b -ᵥ p
hab : ∠ a p b = ∠ a p x
hbc : ∠ b p c = ∠ x p c
⊢ ∠ a p x + ∠ x p c = ∠ a p c

Tactic:
exact angle_add_angle_eq_of_sbtw hx

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
H2 : x = ⟪y, x⟫ • y
⊢ False

Tactic:
rw [H2, norm_smul, hy, Real.norm_eq_abs, mul_one] at hx

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : |⟪y, x⟫| = 1
hy : ‖y‖ = 1
h₁ : ¬x = y
h₂ : ¬x = -y
H2 : x = ⟪y, x⟫ • y
⊢ False
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'
⊢ ¬Collinear ℝ {a', b', c'}

Tactic:
grind only [collinear_iff_eq_or_eq_or_angle_eq_zero_or_angle_eq_pi, angle_self_right,
      angle_self_left, Set.insert_comm, Set.pair_comm]

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

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
he : s.Equilateral
⊢ s.AcuteAngled

Tactic:
intro i₁ i₂ i₃ h₁₂ h₁₃ h₂₃
  rw [he.angle_eq_pi_div_three h₁₂ h₁₃ h₂₃]
  linarith [Real.pi_pos]

Goal state after:
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}
⊢ ¬Collinear ℝ {p₁, p₂, p₃}

Tactic:
have : AffineIndependent ℝ ![p₁, p, p₃] := affineIndependent_iff_not_collinear_set.mpr hn

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}
this : AffineIndependent ℝ ![p₁, p, p₃]
⊢ ¬Collinear ℝ {p₁, p₂, p₃}
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

Goal state before:
pp: case 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
s : Sphere P
p p' : P
hp : p ∈ s
hp' : dist p' s.center < s.radius
⊢ p' ≠ p

Tactic:
rintro rfl
    rw [mem_sphere] at hp
    simp [hp] at hp'

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

Goal state before:
pp: case inl
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 : Fin 3
p : P
h₁₂ : i₁ ≠ i₂
i₃ : Fin 3
h₂ : p ∈ mongePlane t i₃ i₁
h₁ : p ∈ mongePlane t i₃ i₂
h₂₃ : i₂ ≠ i₃
h₁₃ : i₁ ≠ i₃
hi : i₃ ≠ i₁
⊢ p ∈ mongePlane t i₃ i₁

Tactic:
assumption

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

Goal state before:
pp: case 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
i₁ i₂ : Fin 3
p : P
h₁₂ : i₁ ≠ i₂
i₃ : Fin 3
h₂ : p ∈ mongePlane t i₃ i₁
h₁ : p ∈ mongePlane t i₃ i₂
h₂₃ : i₂ ≠ i₃
h₁₃ : i₁ ≠ i₃
hi : i₃ ≠ i₂
⊢ p ∈ mongePlane t i₃ i₂

Tactic:
assumption

Goal state after:
Module: Mathlib.Geometry.Group.Growth.LinearLowerBound

Goal state before:
pp: case inr
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)
⊢ ↑X ^ n = ↑(closure ↑X)

Tactic:
rw [← closure_pow (mod_cast hX₁) hn]

Goal state after:
case inr
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)
⊢ ↑X ^ n = ↑(closure (↑X ^ n))
Module: Mathlib.Geometry.Group.Growth.LinearLowerBound

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
X : Finset G
hX₁ : 1 ∈ X
hX : X.Nontrivial
n : ℕ
hn : n ∈ {n | ↑X ^ (n - 1) ≠ ↑(closure ↑X)}
m : ℕ
hmn : m ≤ n
hm : ↑X ^ (m - 1) = ↑(closure ↑X)
hm₀ : m > 0
⊢ ↑X ^ (n - 1) = ↑X ^ (n - m) * ↑X ^ (m - 1)

Tactic:
← pow_add

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
X : Finset G
hX₁ : 1 ∈ X
hX : X.Nontrivial
n : ℕ
hn : n ∈ {n | ↑X ^ (n - 1) ≠ ↑(closure ↑X)}
m : ℕ
hmn : m ≤ n
hm : ↑X ^ (m - 1) = ↑(closure ↑X)
hm₀ : m > 0
⊢ ↑X ^ (n - 1) = ↑X ^ (n - m + (m - 1))