mathlib-initiative/mathlib-tactics huggingface dataset:
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 (↑((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)
hpm : p ∉ line[ℝ, p₁, p₂]
⊢ dist p ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = dist p ↑((orthogonalProjection line[ℝ, p₁, p₃]) p)

Tactic:
two_zsmul_oangle_orthogonalProjection_self _ hpm (right_mem_affineSpan_pair _ _ _)
          (h'.symm ▸ h₂.symm),

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 : ↑Real.pi = 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)
hpm : p ∉ line[ℝ, p₁, p₂]
⊢ dist p ↑((orthogonalProjection line[ℝ, p₁, p₂]) p) = dist p ↑((orthogonalProjection line[ℝ, p₁, p₃]) p)
Module: Mathlib.Geometry.Euclidean.Basic

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
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
⊢ Submodule.span ℝ (Set.range b) ≤ s.direction

Tactic:
rw [Submodule.span_le, Set.range_subset_iff]
      intro i
      fin_cases i
      · exact vsub_mem_direction hc₂s hc₁s
      · exact vsub_mem_direction hp₂s hp₁s

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

Goal state before:
pp: case neg.refine_2.inl.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
p₁ p₂ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center ≤ s.radius
h : ¬p₁ = p₂
hp₂' : ‖p₂ -ᵥ s.center‖ < dist p₁ s.center
⊢ ‖p₂ -ᵥ s.center‖ < ‖p₁ -ᵥ s.center‖

Tactic:
@dist_eq_norm_vsub V

Goal state after:
case neg.refine_2.inl.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
p₁ p₂ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center ≤ s.radius
h : ¬p₁ = p₂
hp₂' : ‖p₂ -ᵥ s.center‖ < ‖p₁ -ᵥ s.center‖
⊢ ‖p₂ -ᵥ s.center‖ < ‖p₁ -ᵥ s.center‖
Module: Mathlib.Geometry.Euclidean.Sphere.Basic

Goal state before:
pp: case neg.refine_2.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
p₁ p₂ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center ≤ s.radius
h : ¬p₁ = p₂
hp₂' : ‖p₂ -ᵥ s.center‖ = dist p₁ s.center
⊢ ⟪p₂ -ᵥ s.center, p₁ -ᵥ s.center⟫ ≠ ‖p₁ -ᵥ s.center‖ * ‖p₁ -ᵥ s.center‖

Tactic:
@dist_eq_norm_vsub V

Goal state after:
case neg.refine_2.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
p₁ p₂ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center ≤ s.radius
h : ¬p₁ = p₂
hp₂' : ‖p₂ -ᵥ s.center‖ = ‖p₁ -ᵥ s.center‖
⊢ ⟪p₂ -ᵥ s.center, p₁ -ᵥ s.center⟫ ≠ ‖p₁ -ᵥ s.center‖ * ‖p₁ -ᵥ s.center‖
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
s : Sphere P
p : P
h : dist p s.center < s.radius
hp : p ≠ s.center
hb : ℝ ∙ (p -ᵥ s.center) ≠ ⊤
hs : Subsingleton P
⊢ False

Tactic:
simp [Subsingleton.elim p s.center] at hp

Goal state after:
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
as : AffineSubspace ℝ P
h : s.IsTangentAt p as
hq_mem : q ∈ as
h1 : InnerProductGeometry.angle (q -ᵥ p) (p -ᵥ s.center) = π / 2
⊢ InnerProductGeometry.angle (q -ᵥ p) (s.center -ᵥ p) = π / 2

Tactic:
← neg_vsub_eq_vsub_rev _ s.center,

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 q : P
as : AffineSubspace ℝ P
h : s.IsTangentAt p as
hq_mem : q ∈ as
h1 : InnerProductGeometry.angle (q -ᵥ p) (p -ᵥ s.center) = π / 2
⊢ InnerProductGeometry.angle (q -ᵥ p) (-(p -ᵥ s.center)) = π / 2
Module: Mathlib.Geometry.Euclidean.Angle.Sphere

Goal state before:
pp: V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ p₃ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center = s.radius
hp₃ : dist p₃ s.center = s.radius
hp₂p₁ : p₂ ≠ p₁
hp₂p₃ : p₂ ≠ p₃
⊢ ∡ p₁ s.center p₃ = 2 • ∡ p₁ p₂ p₃

Tactic:
@dist_eq_norm_vsub V

Goal state after:
V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ p₃ : P
hp₁ : ‖p₁ -ᵥ s.center‖ = s.radius
hp₂ : ‖p₂ -ᵥ s.center‖ = s.radius
hp₃ : ‖p₃ -ᵥ s.center‖ = s.radius
hp₂p₁ : p₂ ≠ p₁
hp₂p₃ : p₂ ≠ p₃
⊢ ∡ p₁ s.center p₃ = 2 • ∡ p₁ p₂ p₃
Module: Mathlib.Geometry.Euclidean.Angle.Sphere

Goal state before:
pp: V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ p₃ p₄ : P
hp₁ : dist p₁ s.center = s.radius
hp₂ : dist p₂ s.center = s.radius
hp₃ : dist p₃ s.center = s.radius
hp₄ : dist p₄ s.center = s.radius
hp₂p₁ : p₂ ≠ p₁
hp₂p₄ : p₂ ≠ p₄
hp₃p₁ : p₃ ≠ p₁
hp₃p₄ : p₃ ≠ p₄
⊢ 2 • ∡ p₁ p₂ p₄ = 2 • ∡ p₁ p₃ p₄

Tactic:
@dist_eq_norm_vsub V

Goal state after:
V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ p₃ p₄ : P
hp₁ : ‖p₁ -ᵥ s.center‖ = s.radius
hp₂ : ‖p₂ -ᵥ s.center‖ = s.radius
hp₃ : ‖p₃ -ᵥ s.center‖ = s.radius
hp₄ : ‖p₄ -ᵥ s.center‖ = s.radius
hp₂p₁ : p₂ ≠ p₁
hp₂p₄ : p₂ ≠ p₄
hp₃p₁ : p₃ ≠ p₁
hp₃p₄ : p₃ ≠ p₄
⊢ 2 • ∡ p₁ p₂ p₄ = 2 • ∡ p₁ p₃ p₄
Module: Mathlib.Geometry.Euclidean.Angle.Sphere

Goal state before:
pp: V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
h : p₁ ≠ p₂
⊢ ‖midpoint ℝ p₁ p₂ -ᵥ p₁‖ / Real.cos (Real.arctan (∡ p₂ p₁ s.center).tan) =
    ‖midpoint ℝ p₁ p₂ -ᵥ p₁ + (∡ p₂ p₁ s.center).tan • («o».rotation ↑(π / 2)) (midpoint ℝ p₁ p₂ -ᵥ p₁)‖

pp: case h
V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
h : p₁ ≠ p₂
⊢ midpoint ℝ p₁ p₂ -ᵥ p₁ ≠ 0

Tactic:
Real.cos_arctan

Goal state after:
V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
h : p₁ ≠ p₂
⊢ ‖midpoint ℝ p₁ p₂ -ᵥ p₁‖ / (1 / √(1 + (∡ p₂ p₁ s.center).tan ^ 2)) =
    ‖midpoint ℝ p₁ p₂ -ᵥ p₁ + (∡ p₂ p₁ s.center).tan • («o».rotation ↑(π / 2)) (midpoint ℝ p₁ p₂ -ᵥ p₁)‖

case h
V : Type u_3
P : Type u_4
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 : Sphere P
p₁ p₂ : P
hp₁ : p₁ ∈ s
hp₂ : p₂ ∈ s
h : p₁ ≠ p₂
⊢ midpoint ℝ p₁ p₂ -ᵥ p₁ ≠ 0
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: case e'_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
inst✝¹ : Module.Oriented ℝ V (Fin 2)
inst✝ : Fact (Module.finrank ℝ V = 2)
p₁ p₂ p₃ : P
h : 2 • ∡ p₁ p₂ p₃ = 2 • ∡ p₂ p₃ p₁
h0 : ∡ p₃ p₁ p₂ ≠ 0
hpi : ∡ p₃ p₁ p₂ ≠ ↑π
⊢ dist p₁ p₂ = ‖p₂ -ᵥ p₁‖

Tactic:
dist_eq_norm_vsub'

Goal state after:
case e'_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
inst✝¹ : Module.Oriented ℝ V (Fin 2)
inst✝ : Fact (Module.finrank ℝ V = 2)
p₁ p₂ p₃ : P
h : 2 • ∡ p₁ p₂ p₃ = 2 • ∡ p₂ p₃ p₁
h0 : ∡ p₃ p₁ p₂ ≠ 0
hpi : ∡ p₃ p₁ p₂ ≠ ↑π
⊢ ‖p₂ -ᵥ p₁‖ = ‖p₂ -ᵥ p₁‖
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
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
inst✝¹ : Module.Oriented ℝ V (Fin 2)
inst✝ : Fact (Module.finrank ℝ V = 2)
p₁ p₂ p₃ : P
h : 2 • ∡ p₁ p₂ p₃ = 2 • ∡ p₂ p₃ p₁
h0 : ∡ p₃ p₁ p₂ ≠ 0
hpi : ∡ p₃ p₁ p₂ ≠ ↑π
⊢ dist p₁ p₃ = ‖p₃ -ᵥ p₁‖

Tactic:
dist_eq_norm_vsub'

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
inst✝¹ : Module.Oriented ℝ V (Fin 2)
inst✝ : Fact (Module.finrank ℝ V = 2)
p₁ p₂ p₃ : P
h : 2 • ∡ p₁ p₂ p₃ = 2 • ∡ p₂ p₃ p₁
h0 : ∡ p₃ p₁ p₂ ≠ 0
hpi : ∡ p₃ p₁ p₂ ≠ ↑π
⊢ ‖p₃ -ᵥ p₁‖ = ‖p₃ -ᵥ p₁‖
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
m n : ℕ
s : Simplex ℝ P m
e : Fin (m + 1) ≃ Fin (n + 1)
⊢ (s.reindex e).circumsphere = s.circumsphere

Tactic:
refine s.circumsphere_unique_dist_eq.2 _ ⟨?_, ?_⟩ <;> rw [← s.reindex_range_points e]
  · exact (s.reindex e).circumsphere_unique_dist_eq.1.1
  · exact (s.reindex e).circumsphere_unique_dist_eq.1.2

Goal state after:
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
m n : ℕ
s : Simplex ℝ P m
e : Fin (m + 1) ≃ Fin (n + 1)
⊢ (s.reindex e).circumsphere = s.circumsphere

Tactic:
by
  refine s.circumsphere_unique_dist_eq.2 _ ⟨?_, ?_⟩ <;> rw [← s.reindex_range_points e]
  · exact (s.reindex e).circumsphere_unique_dist_eq.1.1
  · exact (s.reindex e).circumsphere_unique_dist_eq.1.2

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

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
a b c : P
hbc : ¬b = c
m : P := midpoint ℝ b c
this : dist b c ≠ 0
hm :
  dist a b ^ 2 * (2⁻¹ * dist b c) + dist a c ^ 2 * (2⁻¹ * dist b c) =
    dist b c * (dist a (midpoint ℝ b c) ^ 2 + 2⁻¹ * dist b c * (2⁻¹ * dist b c))
⊢ dist a b ^ 2 + dist a c ^ 2 = 2 / dist b c * (dist a b ^ 2 * (2⁻¹ * dist b c) + dist a c ^ 2 * (2⁻¹ * dist b c))

Tactic:
by
        field

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

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
⊢ 0 ≤ ⟪x, ortho y x⟫

Tactic:
ortho_eq_sub_inner x hy,

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

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ ⟪y, ortho y x⟫ = 0

Tactic:
rw [ortho, real_inner_comm, Submodule.starProjection_inner_eq_zero]

Goal state after:
case hw
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
⊢ y ∈ ℝ ∙ y
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hz : ‖z‖ = 1
H : angle x z ≠ π
H0 : angle x z = angle x y + angle y z
H1 : ¬angle x z = 0
Hxz : Real.sin (angle x z) ≠ 0
H2 : ¬angle x y = 0
H3 : ¬angle y z = 0
H4 : ¬angle x y = π
H5 : ¬angle y z = π
H6 :
  Real.cos (angle x y) * Real.cos (angle y z) - Real.sin (angle x y) * Real.sin (angle y z) =
    Real.cos (angle x y) * Real.cos (angle y z) +
      Real.sin (angle x y) * Real.sin (angle y z) *
        ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫
Hw : Real.sin (angle x y) * Real.sin (angle y z) ≠ 0
H8 : NormedSpace.normalize (ortho y x) = -NormedSpace.normalize (ortho y z)
H9 : ortho y x ≠ 0
H10 : ortho y z ≠ 0
H11 : ‖NormedSpace.normalize (ortho y x)‖ = 1
H12 : ‖NormedSpace.normalize (ortho y z)‖ = 1
⊢ Real.sin (angle x z) • y = Real.sin (angle y z) • x + Real.sin (angle x y) • z

Tactic:
angle_le_angle_add_angle_aux hx hy

Goal state after:
case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
hz : ‖z‖ = 1
H : angle x z ≠ π
H0 : angle x z = angle x y + angle y z
H1 : ¬angle x z = 0
Hxz : Real.sin (angle x z) ≠ 0
H2 : ¬angle x y = 0
H3 : ¬angle y z = 0
H4 : ¬angle x y = π
H5 : ¬angle y z = π
H6 :
  Real.cos (angle x y) * Real.cos (angle y z) - Real.sin (angle x y) * Real.sin (angle y z) =
    Real.cos (angle x y) * Real.cos (angle y z) +
      Real.sin (angle x y) * Real.sin (angle y z) *
        ⟪NormedSpace.normalize (ortho y x), NormedSpace.normalize (ortho y z)⟫
Hw : Real.sin (angle x y) * Real.sin (angle y z) ≠ 0
H8 : NormedSpace.normalize (ortho y x) = -NormedSpace.normalize (ortho y z)
H9 : ortho y x ≠ 0
H10 : ortho y z ≠ 0
H11 : ‖NormedSpace.normalize (ortho y x)‖ = 1
H12 : ‖NormedSpace.normalize (ortho y z)‖ = 1
⊢ Real.sin (angle x z) • y =
    Real.sin (angle y z) • (Real.cos (angle x y) • y + Real.sin (angle x y) • NormedSpace.normalize (ortho y x)) +
      Real.sin (angle x y) • z
Module: Mathlib.Topology.MetricSpace.Congruence

Goal state before:
pp: ι : Type u_1
P₁ : Type u_3
P₂ : Type u_4
v₁ : ι → P₁
v₂ : ι → P₂
inst✝¹ : PseudoMetricSpace P₁
inst✝ : PseudoMetricSpace P₂
x✝¹ x✝ : ι
⊢ nndist (v₁ x✝¹) (v₁ x✝) = nndist (v₂ x✝¹) (v₂ x✝) ↔ dist (v₁ x✝¹) (v₁ x✝) = dist (v₂ x✝¹) (v₂ x✝)

Tactic:
by rw [dist_nndist, dist_nndist]; norm_cast

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

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
⊢ Sbtw ℝ (t.points i₁) (Simplex.touchpoint t ∅ i₂) (t.points i₃)

Tactic:
rw [← t.mem_interior_face_iff_sbtw h₁₃]
  convert! t.touchpoint_empty_mem_interior_faceOpposite i₂
  rw [Affine.Simplex.faceOpposite]
  convert! rfl using 2
  decide +revert

Goal state after:
Module: Mathlib.Topology.MetricSpace.Similarity

Goal state before:
pp: ι : Type u_1
P₁ : Type u_3
P₂ : Type u_4
v₁ : ι → P₁
v₂ : ι → P₂
inst✝¹ : PseudoMetricSpace P₁
inst✝ : PseudoMetricSpace P₂
⊢ Similar v₁ v₂ ↔ ∃ r, r ≠ 0 ∧ Pairwise fun i₁ i₂ ↦ nndist (v₁ i₁) (v₁ i₂) = r * nndist (v₂ i₁) (v₂ i₂)

Tactic:
simp_rw [similar_iff_exists_pairwise_edist_eq, edist_nndist]
  exact_mod_cast Iff.rfl

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

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
n : ℕ
s : Simplex ℝ P (n + 2)
i₁ i₂ : Fin (n + 3)
h : ¬i₁ = i₂
⊢ ⟪s.mongePoint -ᵥ Finset.centroid ℝ {i₁, i₂}ᶜ s.points, s.points i₁ -ᵥ s.points i₂⟫ = 0

Tactic:
mongePoint_vsub_face_centroid_eq_weightedVSub_of_pointsWithCircumcenter s h,

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
n : ℕ
s : Simplex ℝ P (n + 2)
i₁ i₂ : Fin (n + 3)
h : ¬i₁ = i₂
⊢ ⟪(univ.weightedVSub s.pointsWithCircumcenter) (mongePointVSubFaceCentroidWeightsWithCircumcenter i₁ i₂),
      s.points i₁ -ᵥ s.points i₂⟫ =
    0
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 {s.secondInter p (p' -ᵥ p), p, p'}

Tactic:
exact
    (collinear_insert_iff_of_mem_affineSpan (s.secondInter_vsub_mem_affineSpan _ _)).2
      (collinear_pair ℝ _ _)

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

Goal state before:
pp: case right
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
t₁ t₂ : Triangle ℝ P
i₁ i₂ i₃ j₁ j₂ j₃ : Fin 3
hi₁₂ : i₁ ≠ i₂
hi₁₃ : i₁ ≠ i₃
hi₂₃ : i₂ ≠ i₃
hj₁₂ : j₁ ≠ j₂
hj₁₃ : j₁ ≠ j₃
hj₂₃ : j₂ ≠ j₃
h₁ : t₂.points j₁ = t₁.orthocenter
h₂ : t₂.points j₂ = t₁.points i₂
h₃ : t₂.points j₃ = t₁.points i₃
he : affineSpan ℝ (Set.range t₂.points) = affineSpan ℝ (Set.range t₁.points)
⊢ t₁.points i₁ -ᵥ t₁.points i₂ ∈ (affineSpan ℝ (t₂.points '' {j₂}ᶜ)).directionᗮ

Tactic:
have hu : ({j₂}ᶜ : Set _) = {j₁, j₃} := by grind

Goal state after:
case right
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
t₁ t₂ : Triangle ℝ P
i₁ i₂ i₃ j₁ j₂ j₃ : Fin 3
hi₁₂ : i₁ ≠ i₂
hi₁₃ : i₁ ≠ i₃
hi₂₃ : i₂ ≠ i₃
hj₁₂ : j₁ ≠ j₂
hj₁₃ : j₁ ≠ j₃
hj₂₃ : j₂ ≠ j₃
h₁ : t₂.points j₁ = t₁.orthocenter
h₂ : t₂.points j₂ = t₁.points i₂
h₃ : t₂.points j₃ = t₁.points i₃
he : affineSpan ℝ (Set.range t₂.points) = affineSpan ℝ (Set.range t₁.points)
hu : {j₂}ᶜ = {j₁, j₃}
⊢ t₁.points i₁ -ᵥ t₁.points i₂ ∈ (affineSpan ℝ (t₂.points '' {j₂}ᶜ)).directionᗮ
Module: Mathlib.Geometry.Manifold.IsManifold.InteriorBoundary

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁵ : NormedAddCommGroup E
inst✝⁴ : NormedSpace 𝕜 E
H : Type u_3
inst✝³ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝² : TopologicalSpace M
inst✝¹ : ChartedSpace H M
n : WithTop ℕ∞
inst✝ : IsManifold I n M
e : OpenPartialHomeomorph M H
x : M
hn : n ≠ 0
he : e ∈ atlas H M
hx : x ∈ e.source
⊢ I.IsBoundaryPoint x ↔ ↑(e.extend I) x ∈ frontier (e.extend I).target

Tactic:
rw [← not_iff_not, ← I.isInteriorPoint_iff_not_isBoundaryPoint,
    I.isInteriorPoint_iff_of_mem_atlas hn he hx, mem_interior_iff_notMem_frontier]
  exact (e.extend I).mapsTo <| e.extend_source (I := I) ▸ hx

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

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹¹ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹⁰ : NormedAddCommGroup E
inst✝⁹ : NormedSpace 𝕜 E
H : Type u_3
inst✝⁸ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁷ : TopologicalSpace M
inst✝⁶ : ChartedSpace H M
E' : Type u_5
inst✝⁵ : NormedAddCommGroup E'
inst✝⁴ : NormedSpace 𝕜 E'
H' : Type u_6
inst✝³ : TopologicalSpace H'
N : Type u_7
inst✝² : TopologicalSpace N
inst✝¹ : ChartedSpace H' N
J : ModelWithCorners 𝕜 E' H'
inst✝ : BoundarylessManifold I M
this : ∅.prod univ = ∅
⊢ univ.prod (ModelWithCorners.boundary N) ∪ ∅.prod univ = univ.prod (ModelWithCorners.boundary N)

Tactic:
rw [this, union_empty]

Goal state after:
Module: Mathlib.Geometry.Manifold.VectorBundle.MDifferentiable

Goal state before:
pp: 𝕜 : Type u_1
B : Type u_2
F : Type u_4
E : B → Type u_6
inst✝¹³ : NontriviallyNormedField 𝕜
inst✝¹² : NormedAddCommGroup F
inst✝¹¹ : NormedSpace 𝕜 F
inst✝¹⁰ : TopologicalSpace (TotalSpace F E)
inst✝⁹ : (x : B) → TopologicalSpace (E x)
EB : Type u_7
inst✝⁸ : NormedAddCommGroup EB
inst✝⁷ : NormedSpace 𝕜 EB
HB : Type u_8
inst✝⁶ : TopologicalSpace HB
IB : ModelWithCorners 𝕜 EB HB
inst✝⁵ : TopologicalSpace B
inst✝⁴ : ChartedSpace HB B
inst✝³ : FiberBundle F E
inst✝² : (x : B) → AddCommMonoid (E x)
inst✝¹ : (x : B) → Module 𝕜 (E x)
inst✝ : VectorBundle 𝕜 F E
x : B
⊢ MDiffAt (zeroSection F E) x

Tactic:
unfold zeroSection

Goal state after:
𝕜 : Type u_1
B : Type u_2
F : Type u_4
E : B → Type u_6
inst✝¹³ : NontriviallyNormedField 𝕜
inst✝¹² : NormedAddCommGroup F
inst✝¹¹ : NormedSpace 𝕜 F
inst✝¹⁰ : TopologicalSpace (TotalSpace F E)
inst✝⁹ : (x : B) → TopologicalSpace (E x)
EB : Type u_7
inst✝⁸ : NormedAddCommGroup EB
inst✝⁷ : NormedSpace 𝕜 EB
HB : Type u_8
inst✝⁶ : TopologicalSpace HB
IB : ModelWithCorners 𝕜 EB HB
inst✝⁵ : TopologicalSpace B
inst✝⁴ : ChartedSpace HB B
inst✝³ : FiberBundle F E
inst✝² : (x : B) → AddCommMonoid (E x)
inst✝¹ : (x : B) → Module 𝕜 (E x)
inst✝ : VectorBundle 𝕜 F E
x : B
⊢ (MDiffAt fun x ↦ ⟨x, 0⟩) x
Module: Mathlib.Geometry.Manifold.VectorBundle.Hom

Goal state before:
pp: 𝕜 : Type u_1
B : Type u_2
F₁ : Type u_3
F₂ : Type u_4
M : Type u_6
inst✝²⁸ : NontriviallyNormedField 𝕜
E₁ : B → Type u_7
inst✝²⁷ : (x : B) → AddCommGroup (E₁ x)
inst✝²⁶ : (x : B) → Module 𝕜 (E₁ x)
inst✝²⁵ : NormedAddCommGroup F₁
inst✝²⁴ : NormedSpace 𝕜 F₁
inst✝²³ : TopologicalSpace (TotalSpace F₁ E₁)
inst✝²² : (x : B) → TopologicalSpace (E₁ x)
E₂ : B → Type u_8
inst✝²¹ : (x : B) → AddCommGroup (E₂ x)
inst✝²⁰ : (x : B) → Module 𝕜 (E₂ x)
inst✝¹⁹ : NormedAddCommGroup F₂
inst✝¹⁸ : NormedSpace 𝕜 F₂
inst✝¹⁷ : TopologicalSpace (TotalSpace F₂ E₂)
inst✝¹⁶ : (x : B) → TopologicalSpace (E₂ x)
EB : Type u_10
inst✝¹⁵ : NormedAddCommGroup EB
inst✝¹⁴ : NormedSpace 𝕜 EB
HB : Type u_11
inst✝¹³ : TopologicalSpace HB
IB : ModelWithCorners 𝕜 EB HB
inst✝¹² : TopologicalSpace B
inst✝¹¹ : ChartedSpace HB B
EM : Type u_12
inst✝¹⁰ : NormedAddCommGroup EM
inst✝⁹ : NormedSpace 𝕜 EM
HM : Type u_13
inst✝⁸ : TopologicalSpace HM
IM : ModelWithCorners 𝕜 EM HM
inst✝⁷ : TopologicalSpace M
inst✝⁶ : ChartedSpace HM M
inst✝⁵ : FiberBundle F₁ E₁
inst✝⁴ : VectorBundle 𝕜 F₁ E₁
inst✝³ : FiberBundle F₂ E₂
inst✝² : VectorBundle 𝕜 F₂ E₂
b : M → B
v : (x : M) → E₁ (b x)
s : Set M
x : M
inst✝¹ : ∀ (x : B), IsTopologicalAddGroup (E₂ x)
inst✝ : ∀ (x : B), ContinuousSMul 𝕜 (E₂ x)
ϕ : (x : M) → E₁ (b x) →L[𝕜] E₂ (b x)
hϕ : MDiffAt[s] (T% ϕ) x
hv : MDiffAt[s] (T% v) x
⊢ (MDiffAt[s] fun m ↦ ⟨b m, (ϕ m) (v m)⟩) x

Tactic:
by
  simp only [mdifferentiableWithinAt_hom_bundle] at hϕ
  exact hϕ.2.clm_apply_of_inCoordinates hv hϕ.1

Goal state after: