mathlib-initiative/mathlib-tactics huggingface dataset:
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)
s : AffineSubspace ℝ P
p₁ p₂ p₃ p₄ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
hp₃p₄ : s.SSameSide p₃ p₄
h : ¬p₁ = p₂
sp : Set (P × P × P) := (fun p ↦ (p₁, p, p₂)) '' {p | s.SSameSide p₃ p}
hc : IsConnected sp
hp' : s.SSameSide p₃ p₂
⊢ False

Tactic:
· exact hp'.2.2 hp₂

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
hvi : ⟪v, v⟫ ≠ 0
hd : discrim ⟪v, v⟫ (2 * ⟪v, p₁ -ᵥ p₂⟫) 0 = 2 * ⟪v, p₁ -ᵥ p₂⟫ * (2 * ⟪v, p₁ -ᵥ p₂⟫)
⊢ r = (-(2 * ⟪v, p₁ -ᵥ p₂⟫) + 2 * ⟪v, p₁ -ᵥ p₂⟫) / (2 * ⟪v, v⟫) ∨
      r = (-(2 * ⟪v, p₁ -ᵥ p₂⟫) - 2 * ⟪v, p₁ -ᵥ p₂⟫) / (2 * ⟪v, v⟫) ↔
    r = 0 ∨ r = -2 * ⟪v, p₁ -ᵥ p₂⟫ / ⟪v, v⟫

Tactic:
neg_add_cancel,

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
v : V
p₁ p₂ : P
hv : v ≠ 0
r : ℝ
hvi : ⟪v, v⟫ ≠ 0
hd : discrim ⟪v, v⟫ (2 * ⟪v, p₁ -ᵥ p₂⟫) 0 = 2 * ⟪v, p₁ -ᵥ p₂⟫ * (2 * ⟪v, p₁ -ᵥ p₂⟫)
⊢ r = 0 / (2 * ⟪v, v⟫) ∨ r = (-(2 * ⟪v, p₁ -ᵥ p₂⟫) - 2 * ⟪v, p₁ -ᵥ p₂⟫) / (2 * ⟪v, v⟫) ↔
    r = 0 ∨ r = -2 * ⟪v, p₁ -ᵥ p₂⟫ / ⟪v, v⟫
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)
s : AffineSubspace ℝ P
p₁ p₂ p₃ p₄ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
hp₃p₄ : s.SOppSide p₃ p₄
⊢ (∡ p₁ p₄ p₂).sign = -(∡ p₁ p₃ p₂).sign

Tactic:
have hp₁p₃ : p₁ ≠ p₃ := by rintro rfl; exact hp₃p₄.left_notMem hp₁

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
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
s : AffineSubspace ℝ P
p₁ p₂ p₃ p₄ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
hp₃p₄ : s.SOppSide p₃ p₄
hp₁p₃ : p₁ ≠ p₃
⊢ (∡ p₁ p₄ p₂).sign = -(∡ p₁ p₃ p₂).sign
Module: Mathlib.Geometry.Euclidean.SignedDist

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
n : ℕ
inst✝¹ : NeZero n
s : Simplex ℝ P n
m : ℕ
inst✝ : NeZero m
e : Fin (n + 1) ≃ Fin (m + 1)
j : Fin (m + 1)
⊢ (s.reindex e).signedInfDist j = s.signedInfDist (e.symm j)

Tactic:
simp_rw [signedInfDist, reindex_points, Set.image_comp, Set.image_compl_eq e.symm.bijective,
    Set.image_singleton, Function.comp_apply]

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

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
i : Fin (n + 1)
w : Fin (n + 1) → ℝ
h : ∑ i, w i = 1
⊢ ↑(s.signedInfDist i) ((Finset.affineCombination ℝ Finset.univ s.points) w) =
    w i * ‖s.points i -ᵥ ↑((s.faceOpposite i).orthogonalProjectionSpan (s.points i))‖

Tactic:
Finset.map_affineCombination _ _ _ h,

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
i : Fin (n + 1)
w : Fin (n + 1) → ℝ
h : ∑ i, w i = 1
⊢ ((Finset.affineCombination ℝ Finset.univ (⇑↑(s.signedInfDist i) ∘ s.points)) fun i ↦ w i) =
    w i * ‖s.points i -ᵥ ↑((s.faceOpposite i).orthogonalProjectionSpan (s.points i))‖
Module: Mathlib.Geometry.Euclidean.Angle.Bisector

Goal state before:
pp: case inr
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
hp : p ≠ p₁
⊢ dist p ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = dist p ↑((orthogonalProjection line[ℝ, p₁, p₃]) p)

Tactic:
rw [← h'] at h hp

Goal state after:
case inr
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 (↑((orthogonalProjection line[ℝ, p₁, p₂]) p)) p = 2 • ∡ p (↑((orthogonalProjection line[ℝ, p₁, p₂]) p)) p₃
h' : ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = p₁
hp : p ≠ ↑((orthogonalProjection line[ℝ, p₁, p₂]) p)
⊢ dist p ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = dist p ↑((orthogonalProjection line[ℝ, p₁, p₃]) p)
Module: Mathlib.Geometry.Euclidean.Sphere.Basic

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 : Set P
hs : Cospherical s
p₁ p₂ p₃ : P
h₁ : p₁ ∈ s
h₂ : p₂ ∈ s
h₃ : p₃ ∈ s
h₁₂ : p₁ ≠ p₂
h₁₃ : p₁ ≠ p₃
h₂₃ : p₂ ≠ p₃
⊢ Function.Injective ![p₁, p₂, p₃]

Tactic:
· simp only [Matrix.vecCons, Fin.cons_injective_iff]
    simp [h₁₂, h₁₃, h₂₃, Function.Injective, eq_iff_true_of_subsingleton]

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

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

Tactic:
· rw [dist_comm] at h
      have ha : |s₂.radius - s₁.radius| = s₂.radius - s₁.radius := by
        refine abs_of_nonneg ?_
        rw [← h]
        exact dist_nonneg
      have hr0 : s₂.radius - s₁.radius ≠ 0 := by
        intro hr0
        rw [hr0, dist_eq_zero] at h
        exact h0 h.symm
      refine ⟨AffineMap.lineMap s₂.center s₁.center (s₂.radius / (s₂.radius - s₁.radius)),
              ?_, ?_, ?_⟩
      · simp only [mem_sphere, dist_lineMap_right, Real.norm_eq_abs, h, one_sub_div hr0, abs_div,
          sub_sub_cancel_left, abs_neg, abs_of_nonneg h₁, ha]
        field
      · simp only [mem_sphere, dist_lineMap_left, norm_div, Real.norm_eq_abs, h, ha,
          abs_of_nonneg h₂]
        field
      · rw [wbtw_iff_left_eq_or_right_mem_image_Ici]
        simp only [Ne.symm h0, Set.mem_image, Set.mem_Ici, AffineMap.lineMap_eq_lineMap_iff,
          false_or, exists_eq_right]
        rw [one_le_div]
        · linarith
        · rw [← h]
          simp [Ne.symm h0]

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

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
hf2 : Fact (Module.finrank ℝ V = 2)
s : Sphere P
p : P
hp : dist p s.center < s.radius
hpc : p ≠ s.center
v : ↥(s.orthRadius p).direction
hv : ∀ (w : ↥(s.orthRadius p).direction), ∃ c, c • v = w
hv0 : ↑v ≠ 0
⊢ dist p s.center ^ 2 < s.radius ^ 2

Tactic:
sq_lt_sq,

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
hf2 : Fact (Module.finrank ℝ V = 2)
s : Sphere P
p : P
hp : dist p s.center < s.radius
hpc : p ≠ s.center
v : ↥(s.orthRadius p).direction
hv : ∀ (w : ↥(s.orthRadius p).direction), ∃ c, c • v = w
hv0 : ↑v ≠ 0
⊢ |dist p s.center| < |s.radius|
Module: Mathlib.Geometry.Euclidean.Angle.Sphere

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
p₁ p₂ p₃ : P
s : Sphere P
inst✝ : Fact (finrank ℝ V = 2)
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
hp₃ : p₃ ∈ s
hne₁₂ : p₁ ≠ p₂
hne₂₃ : p₂ ≠ p₃
hangle : 0 = π / 2
this : FiniteDimensional ℝ V
h : p₁ = p₃
⊢ False

Tactic:
linarith [Real.pi_pos]

Goal state after:
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.excenter signs) (s.points i) ↔
    0 < s.excenterWeights signs i

Tactic:
rw [excenter_eq_affineCombination,
    s.sSameSide_affineSpan_faceOpposite_point_right_iff h.sum_excenterWeights_eq_one]

Goal state after:
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 : P
hb : a ≠ b
hc : a ≠ c
pb : ¬p = b
pc : ¬p = c
ea : ∠ b a c + ∠ a c b + ∠ c b a = π
eb : ∠ b a p + ∠ a p b + ∠ c b a = π
ec : ∠ a c p + ∠ c p a + ∠ p a c = π
hp : ∠ b p c = π
hp' : ∠ c p b = π
⊢ ∠ b a p + ∠ p a c = ∠ b a c

Tactic:
rw [angle_eq_angle_of_angle_eq_pi a hp', angle_comm c p a] at ec

Goal state after:
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 : P
hb : a ≠ b
hc : a ≠ c
pb : ¬p = b
pc : ¬p = c
ea : ∠ b a c + ∠ a c b + ∠ c b a = π
eb : ∠ b a p + ∠ a p b + ∠ c b a = π
ec : ∠ a c b + ∠ a p c + ∠ p a c = π
hp : ∠ b p c = π
hp' : ∠ c p b = π
⊢ ∠ b a p + ∠ p a c = ∠ b a c
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case inl
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hy : ‖y‖ = 1
h₁ : ¬x = y
h₂ : ¬x = -y
H2 : x = ⟪y, x⟫ • y
hx : ⟪y, x⟫ = 1
⊢ False

Tactic:
simp [*] at H2

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

Goal state before:
pp: case inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hy : ‖y‖ = 1
h₁ : ¬x = y
h₂ : ¬x = -y
H2 : x = ⟪y, x⟫ • y
hx : ⟪y, x⟫ = -1
⊢ False

Tactic:
simp [*] at H2

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

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
hp : s.excenter signs ∈ affineSpan ℝ (Set.range s.points)
i : Fin (n + 1)
⊢ (s.signedInfDist i) (s.excenter signs) =
    (if i ∈ signs then -1 else 1) * (↑(SignType.sign (∑ j, s.excenterWeightsUnnorm signs j)) * s.exradius signs)

Tactic:
rw [h.signedInfDist_excenter]

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
hp : s.excenter signs ∈ affineSpan ℝ (Set.range s.points)
i : Fin (n + 1)
⊢ (if i ∈ signs then -1 else 1) * ↑(SignType.sign (∑ j, s.excenterWeightsUnnorm signs j)) * s.exradius signs =
    (if i ∈ signs then -1 else 1) * (↑(SignType.sign (∑ j, s.excenterWeightsUnnorm signs j)) * s.exradius signs)
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
⊢ ⟪x, NormedSpace.normalize (ortho y x)⟫ = Real.sin (angle x y)

Tactic:
have H : ⟪x, normalize (ortho y x)⟫ ^ 2 = Real.sin (angle x y) ^ 2 := by
    simp [Real.sin_sq, ← inner_eq_cos_angle_of_norm_eq_one hx hy,
      ← inner_normalized_ortho_sq_add_inner_sq_eq_one hx hy]
  rw [sq_eq_sq_iff_abs_eq_abs, abs_of_nonneg (sin_angle_nonneg x y)] at H
  have H0 : 0 ≤ ⟪x, normalize (ortho y x)⟫ := by
    rw [NormedSpace.normalize, real_inner_smul_right]
    exact Left.mul_nonneg (inv_nonneg_of_nonneg (norm_nonneg (ortho y x)))
      (inner_ortho_nonneg hx hy)
  simp_all [abs_of_nonneg H0]

Goal state after:
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 j : Fin (n + 1)
hij : s.touchpoint signs i = s.touchpoint signs j
hne : ¬i = j
⊢ False

Tactic:
by_cases hn1 : n = 1

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i j : Fin (n + 1)
hij : s.touchpoint signs i = s.touchpoint signs j
hne : ¬i = j
hn1 : n = 1
⊢ False

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i j : Fin (n + 1)
hij : s.touchpoint signs i = s.touchpoint signs j
hne : ¬i = j
hn1 : ¬n = 1
⊢ False
Module: Mathlib.Geometry.Euclidean.Circumcenter

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
s : AffineSubspace ℝ P
ps : Set P
h : ps ⊆ ↑s
inst✝¹ : Nonempty ↥s
n : ℕ
inst✝ : FiniteDimensional ℝ ↥s.direction
hd : finrank ℝ ↥s.direction = n
c : P
hc : c ∈ s
r : ℝ
hcr : ∀ p ∈ ps, dist p c = r
sx : Simplex ℝ P n
hsxps : Set.range sx.points ⊆ ps
⊢ Fintype.card (Fin (n + 1)) = finrank ℝ ↥s.direction + 1

Tactic:
simp [hd]

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

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
ps : Set P
n : ℕ
inst✝ : FiniteDimensional ℝ V
hd : finrank ℝ V = n
hc : Cospherical ps
⊢ ∃ r, ∀ (sx : Simplex ℝ P n), Set.range sx.points ⊆ ps → sx.circumradius = r

Tactic:
rw [← finrank_top, ← direction_top ℝ V P] at hd
  refine exists_circumradius_eq_of_cospherical_subset ?_ hd hc
  exact Set.subset_univ _

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

Goal state before:
pp: case pos
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
h₂₃₁ : ∠ p₂ p₃ p₁ ≤ ∠ p₁ p₂ p₃
h₃₁₂ : ∠ p₃ p₁ p₂ ≤ ∠ p₁ p₂ p₃
h : p₂ = p₁
⊢ π / 3 ≤ π / 2

Tactic:
linarith [Real.pi_pos]

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

Goal state before:
pp: case pos
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
h₂₃₁ : ∠ p₂ p₃ p₁ ≤ ∠ p₁ p₂ p₃
h₃₁₂ : ∠ p₃ p₁ p₂ ≤ ∠ p₁ p₂ p₃
hne : ∠ p₁ p₂ p₃ ≠ ∠ p₂ p₃ p₁ ∨ ∠ p₁ p₂ p₃ ≠ ∠ p₃ p₁ p₂ ∨ ∠ p₂ p₃ p₁ ≠ ∠ p₃ p₁ p₂
h : p₂ = p₁
⊢ π / 3 < π / 2

Tactic:
linarith [Real.pi_pos]

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

Goal state before:
pp: case pos
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
p₂ p₃ : P
h₂₃₁ : π / 2 ≤ 0
hnd : ¬p₂ = p₃
⊢ π / 2 ≤ π / 3

Tactic:
linarith [Real.pi_pos]

Goal state after:
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
p₂ p₃ : P
h₂₃₁ : π / 2 ≤ 0
h₂₃ : ¬p₂ = p₃
⊢ π / 2 < π / 3

Tactic:
linarith [Real.pi_pos]

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 = 0
hy : ¬y = 0
⊢ angle x z ≤ angle x y + angle y z

Tactic:
by_cases hz : z = 0

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ¬x = 0
hy : ¬y = 0
hz : z = 0
⊢ angle x z ≤ angle x y + angle y z

case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ¬x = 0
hy : ¬y = 0
hz : ¬z = 0
⊢ angle x z ≤ angle x y + angle y z
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 z : V
kx ky kz : ℝ≥0
hy : ky ≠ 0
hlincomb : ky • y = kx • x + kz • z
⊢ y ∈ Submodule.span ℝ≥0 {x, z}

Tactic:
have h₁ : ky • y ∈ Submodule.span ℝ≥0 {x, z} := by
    rw [Submodule.mem_span_pair]; grind
  rwa [Submodule.smul_mem_iff _ hy] at h₁

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
hy : y ≠ 0
h : angle x z = angle x y + angle y z
hxz₁ : ¬angle x z = π
hxz₂ : ¬angle x z = 0
h_sin_xz : Real.sin (angle x z) ≠ 0
hx : ¬x = 0
⊢ y ∈ Submodule.span ℝ≥0 {x, z}

Tactic:
by_cases hz : z = 0

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hy : y ≠ 0
h : angle x z = angle x y + angle y z
hxz₁ : ¬angle x z = π
hxz₂ : ¬angle x z = 0
h_sin_xz : Real.sin (angle x z) ≠ 0
hx : ¬x = 0
hz : z = 0
⊢ y ∈ Submodule.span ℝ≥0 {x, z}

case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hy : y ≠ 0
h : angle x z = angle x y + angle y z
hxz₁ : ¬angle x z = π
hxz₂ : ¬angle x z = 0
h_sin_xz : Real.sin (angle x z) ≠ 0
hx : ¬x = 0
hz : ¬z = 0
⊢ y ∈ Submodule.span ℝ≥0 {x, z}
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 z : V
hy : y ≠ 0
⊢ angle x z = angle x y + angle y z ↔ angle x z = π ∨ y ∈ Submodule.span ℝ≥0 {x, z}

Tactic:
by
  constructor <;> rintro h
  · by_cases hxz₁ : angle x z = π
    · tauto
    right
    by_cases hxz₂ : angle x z = 0
    · have hxy : angle x y = 0 := by grind [angle_nonneg]
      rw [angle_eq_zero_iff] at hxy hxz₂
      obtain ⟨_, ⟨r2, ⟨hr2, rfl⟩⟩⟩ := hxy
      lift r2 to ℝ≥0 using hr2.le
      exact Submodule.smul_mem _ _ (Submodule.mem_span_of_mem (by simp))
    have h_sin_xz : Real.sin (angle x z) ≠ 0 := by
      grind [sin_eq_zero_iff_angle_eq_zero_or_angle_eq_pi]
    by_cases hx : x = 0
    · subst x; simp only [angle_zero_left, left_eq_add] at h
      rw [angle_eq_zero_iff] at h
      obtain ⟨_, ⟨r, ⟨hr, rfl⟩⟩⟩ := h
      lift r to ℝ≥0 using hr.le
      rw [← NNReal.smul_def, Submodule.span_insert_zero, Submodule.span_singleton_smul_eq]
      · simp
      norm_cast at hr
      grind [isUnit_iff_ne_zero]
    by_cases hz : z = 0
    · subst z; simp only [angle_zero_right, right_eq_add] at h
      rw [angle_eq_zero_iff] at h
      obtain ⟨_, ⟨r, ⟨hr, rfl⟩⟩⟩ := h
      lift r to ℝ≥0 using hr.le
      exact Submodule.smul_mem _ _ (Submodule.mem_span_of_mem (by simp))
    have hnneg₁ : 0 ≤ Real.sin (angle y z) / ‖x‖ := by
      grind [sin_angle_nonneg, norm_nonneg, div_nonneg_iff, mul_nonneg_iff]
    have hnneg₂ : 0 ≤ Real.sin (angle x y) / ‖z‖ := by
      grind [sin_angle_nonneg, norm_nonneg, div_nonneg_iff, mul_nonneg_iff]
    have hnneg₃ : 0 ≤ Real.sin (angle x z) / ‖y‖ := by
      grind [sin_angle_nonneg, norm_nonneg, div_nonneg_iff, mul_nonneg_iff]
    have hnonzero : (⟨Real.sin (angle x z) / ‖y‖, hnneg₃⟩ : ℝ≥0) ≠ 0 := by
      simp; grind
    have h₁ := angle_expression_of_angle_eq_angle_sum (norm_normalize_eq_one_iff.mpr hx)
        (norm_normalize_eq_one_iff.mpr hy) (norm_normalize_eq_one_iff.mpr hz)
    simp only [angle_normalize_right, angle_normalize_left] at h₁
    have h₂ := h₁ hxz₁ h
    have h₃ : (⟨_, hnneg₃⟩ : ℝ≥0) • y = (⟨_, hnneg₁⟩ : ℝ≥0) • x + (⟨_, hnneg₂⟩ : ℝ≥0) • z := by
      simp only [NormedSpace.normalize, ← smul_assoc, smul_eq_mul, Nonneg.mk_smul] at h₂ ⊢
      exact h₂
    exact mem_span_of_linear_combination hnonzero h₃
  · obtain h | h := h
    · grind [angle_add_angle_eq_pi_of_angle_eq_pi, angle_comm]
    · exact angle_eq_angle_add_add_angle_add_of_mem_span hy h

Goal state after:
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
n : ℕ
hn : NeZero n
s : Simplex ℝ P n
i : Fin (n + 1)
⊢ ⅟2 • (s.faceOppositeCentroid i -ᵥ s.circumcenter) +
      ⅟2 •
        (((↑n)⁻¹ • (s.points i -ᵥ ((↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter)) +ᵥ
            (↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter) -ᵥ
          s.circumcenter) =
    ((↑n + 1) / ↑n) • (s.centroid -ᵥ s.circumcenter)

Tactic:
by_cases hn1 : n = 1

Goal state after:
case pos
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
hn : NeZero n
s : Simplex ℝ P n
i : Fin (n + 1)
hn1 : n = 1
⊢ ⅟2 • (s.faceOppositeCentroid i -ᵥ s.circumcenter) +
      ⅟2 •
        (((↑n)⁻¹ • (s.points i -ᵥ ((↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter)) +ᵥ
            (↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter) -ᵥ
          s.circumcenter) =
    ((↑n + 1) / ↑n) • (s.centroid -ᵥ s.circumcenter)

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
n : ℕ
hn : NeZero n
s : Simplex ℝ P n
i : Fin (n + 1)
hn1 : ¬n = 1
⊢ ⅟2 • (s.faceOppositeCentroid i -ᵥ s.circumcenter) +
      ⅟2 •
        (((↑n)⁻¹ • (s.points i -ᵥ ((↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter)) +ᵥ
            (↑(n + 1) / ↑(n - 1)) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter) -ᵥ
          s.circumcenter) =
    ((↑n + 1) / ↑n) • (s.centroid -ᵥ s.circumcenter)
Module: Mathlib.Geometry.Euclidean.MongePoint

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 ⋯).mongePoint = f s.mongePoint

Tactic:
mongePoint_eq_smul_vsub_vadd_circumcenter

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
⊢ (↑(n + 1) / ↑(n - 1)) •
        (Finset.centroid ℝ univ (s.map f.toAffineMap ⋯).points -ᵥ (s.map f.toAffineMap ⋯).circumcenter) +ᵥ
      (s.map f.toAffineMap ⋯).circumcenter =
    f ((↑(n + 1) / ↑(n - 1)) • (Finset.centroid ℝ univ s.points -ᵥ s.circumcenter) +ᵥ s.circumcenter)