mathlib-initiative/mathlib-tactics huggingface dataset:
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 a' b' c' : P
r : ℝ
h : ∠ a' b' c' = ∠ a b c
hab : dist a' b' = r * dist a b
hcb : dist c' b' = r * dist c b
⊢ dist a' b' ^ 2 + dist c' b' ^ 2 - 2 * dist a' b' * dist c' b' * Real.cos (∠ a' b' c') =
    r ^ 2 * (dist a b ^ 2 + dist c b ^ 2 - 2 * dist a b * dist c b * Real.cos (∠ a b c))

Tactic:
h,

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
a b c a' b' c' : P
r : ℝ
h : ∠ a' b' c' = ∠ a b c
hab : dist a' b' = r * dist a b
hcb : dist c' b' = r * dist c b
⊢ dist a' b' ^ 2 + dist c' b' ^ 2 - 2 * dist a' b' * dist c' b' * Real.cos (∠ a b c) =
    r ^ 2 * (dist a b ^ 2 + dist c b ^ 2 - 2 * dist a b * dist c b * Real.cos (∠ a b c))
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
p : P
hp : p ∈ affineSpan ℝ (Set.range s.points)
signs : Finset (Fin (n + 1))
⊢ s.ExcenterExists signs ∧ p = s.excenter signs →
    ∃ r, ∀ (i : Fin (n + 1)), (s.signedInfDist i) p = (if i ∈ signs then -1 else 1) * r

Tactic:
· rintro ⟨h, rfl⟩
    refine ⟨SignType.sign (∑ j, s.excenterWeightsUnnorm signs j) * (s.exradius signs), fun i ↦ ?_⟩
    rw [h.signedInfDist_excenter]
    simp

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
a b c : P
h : ¬Collinear ℝ {a, b, c}
hsin : Real.sin (∠ a b c) * dist a b = Real.sin (∠ a c b) * dist a c
hac : dist a c > 0
hsinabc : Real.sin (∠ a b c) ≥ 0
h1 : ∠ a c b < ∠ a b c
h2 : ∠ a b c ≤ π / 2
⊢ dist a b < dist a c

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
h : ¬Collinear ℝ {a, b, c}
hsin : Real.sin (∠ a b c) * dist a b = Real.sin (∠ a c b) * dist a c
hac : dist a c > 0
hsinabc : Real.sin (∠ a b c) ≥ 0
h1 : ∠ a c b < ∠ a b c
h2 : π / 2 < ∠ a b c
⊢ dist a b < dist a c

Tactic:
· have h3 : Real.sin (∠ a c b) < Real.sin (∠ a b c) := by
      exact Real.sin_lt_sin_of_lt_of_le_pi_div_two (by linarith [angle_nonneg a c b]) h2 h1
    by_contra! w
    have h4 : Real.sin (∠ a c b) * dist a c < Real.sin (∠ a b c) * dist a b := by
      exact mul_lt_mul h3 w hac hsinabc
    linarith

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
h : ¬Collinear ℝ {a, b, c}
hsin : Real.sin (∠ a b c) * dist a b = Real.sin (∠ a c b) * dist a c
hac : dist a c > 0
hsinabc : Real.sin (∠ a b c) ≥ 0
h1 : ∠ a c b < ∠ a b c
h2 : π / 2 < ∠ a b c
⊢ dist a b < dist a c
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 ≤ ∠ p₁ p₂ p₃

Tactic:
h,

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
p₁ p₂ p₃ : P
h₂₃₁ : ∠ p₂ p₃ p₁ ≤ ∠ p₁ p₂ p₃
h₃₁₂ : ∠ p₃ p₁ p₂ ≤ ∠ p₁ p₂ p₃
h : p₂ = p₁
⊢ π / 3 ≤ ∠ p₁ p₁ p₃
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 < ∠ p₁ p₂ p₃

Tactic:
h,

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
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 < ∠ p₁ p₁ p₃
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
h_mem : ∃ a b, a • x + b • z = y
⊢ angle x z = angle x y + angle y z

Tactic:
obtain ⟨kx, kz, rfl⟩ := h_mem

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x z : V
kx kz : ℝ≥0
hy : kx • x + kz • z ≠ 0
⊢ angle x z = angle x (kx • x + kz • z) + angle (kx • x + kz • z) z
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case inr.inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x z : V
kx kz : ℝ≥0
hy : kx • x + kz • z ≠ 0
hkx : 0 < kx
hkz : 0 < kz
⊢ angle x z = angle x (kx • x + kz • z) + angle (kx • x + kz • z) z

Tactic:
rw [angle_comm (_ + _) z]

Goal state after:
case inr.inr
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x z : V
kx kz : ℝ≥0
hy : kx • x + kz • z ≠ 0
hkx : 0 < kx
hkz : 0 < kz
⊢ angle x z = angle x (kx • x + kz • z) + angle z (kx • x + kz • z)
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
y z : V
hy : y ≠ 0
hxz₁ : ¬angle 0 z = π
hxz₂ : ¬angle 0 z = 0
h_sin_xz : Real.sin (angle 0 z) ≠ 0
h : y ≠ 0 ∧ ∃ r, 0 < r ∧ z = r • y
⊢ y ∈ Submodule.span ℝ≥0 {0, z}

Tactic:
obtain ⟨_, ⟨r, ⟨hr, rfl⟩⟩⟩ := h

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
y : V
hy left✝ : y ≠ 0
r : ℝ
hr : 0 < r
hxz₁ : ¬angle 0 (r • y) = π
hxz₂ : ¬angle 0 (r • y) = 0
h_sin_xz : Real.sin (angle 0 (r • y)) ≠ 0
⊢ y ∈ Submodule.span ℝ≥0 {0, r • y}
Module: Mathlib.Geometry.Euclidean.Angle.Unoriented.TriangleInequality

Goal state before:
pp: case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hy : y ≠ 0
hx : ¬x = 0
hxz₁ : ¬angle x 0 = π
hxz₂ : ¬angle x 0 = 0
h_sin_xz : Real.sin (angle x 0) ≠ 0
h : x ≠ 0 ∧ ∃ r, 0 < r ∧ y = r • x
⊢ y ∈ Submodule.span ℝ≥0 {x, 0}

Tactic:
obtain ⟨_, ⟨r, ⟨hr, rfl⟩⟩⟩ := h

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x : V
hx : ¬x = 0
hxz₁ : ¬angle x 0 = π
hxz₂ : ¬angle x 0 = 0
h_sin_xz : Real.sin (angle x 0) ≠ 0
left✝ : x ≠ 0
r : ℝ
hr : 0 < r
hy : r • x ≠ 0
⊢ r • x ∈ Submodule.span ℝ≥0 {x, 0}
Module: Mathlib.Geometry.Euclidean.Incenter

Goal state before:
pp: case inr.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
⊢ Simplex.ExcenterExists t ∅ᶜ

Tactic:
Simplex.excenterExists_compl

Goal state after:
case inr.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
⊢ Simplex.ExcenterExists t ∅
Module: Mathlib.Geometry.Euclidean.Incenter

Goal state before:
pp: case inr.inr.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
i : Fin 3
⊢ Simplex.ExcenterExists t {i}ᶜ

Tactic:
Simplex.excenterExists_compl

Goal state after:
case inr.inr.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
i : Fin 3
⊢ Simplex.ExcenterExists t {i}
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
⊢ Simplex.face t ⋯ = Simplex.faceOpposite t i₂

Tactic:
rw [Affine.Simplex.faceOpposite]

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
⊢ Simplex.face t ⋯ = Simplex.face t ⋯
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
hw : Simplex.touchpointWeights t {i₁} i₂ i₁ + Simplex.touchpointWeights t {i₁} i₂ i₃ = 1
h :
  Simplex.touchpointWeights t {i₁} i₂ =
    Finset.affineCombinationLineMapWeights i₁ i₃ (Simplex.touchpointWeights t {i₁} i₂ i₃)
⊢ Sbtw ℝ ((Finset.affineCombination ℝ Finset.univ t.points) (Simplex.touchpointWeights t {i₁} i₂)) (t.points i₃)
    (t.points i₁)

Tactic:
h,

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
hw : Simplex.touchpointWeights t {i₁} i₂ i₁ + Simplex.touchpointWeights t {i₁} i₂ i₃ = 1
h :
  Simplex.touchpointWeights t {i₁} i₂ =
    Finset.affineCombinationLineMapWeights i₁ i₃ (Simplex.touchpointWeights t {i₁} i₂ i₃)
⊢ Sbtw ℝ
    ((Finset.affineCombination ℝ Finset.univ t.points)
      (Finset.affineCombinationLineMapWeights i₁ i₃ (Simplex.touchpointWeights t {i₁} i₂ i₃)))
    (t.points i₃) (t.points i₁)
Module: Mathlib.Geometry.Euclidean.NinePointCircle

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
n : ℕ
s : Simplex ℝ P n
i : Fin (n + 1)
hn : n = 0
⊢ s.points i -ᵥ s.mongePoint - (↑n)⁻¹ • (s.points i -ᵥ s.mongePoint) = ((↑n - 1) / ↑n) • (s.points i -ᵥ s.mongePoint)

Tactic:
obtain rfl := hn

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
s : Simplex ℝ P 0
i : Fin (0 + 1)
⊢ s.points i -ᵥ s.mongePoint - (↑0)⁻¹ • (s.points i -ᵥ s.mongePoint) = ((↑0 - 1) / ↑0) • (s.points i -ᵥ s.mongePoint)
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
⊢ (↑(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)

Tactic:
← Simplex.centroid,

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)) • ((s.map f.toAffineMap ⋯).centroid -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)
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
S : AffineSubspace ℝ P
hS : affineSpan ℝ (Set.range s.points) ≤ S
this : Nonempty ↥S
⊢ ↑((↑(n + 1) / ↑(n - 1)) • (Finset.centroid ℝ univ (s.restrict S hS).points -ᵥ (s.restrict S hS).circumcenter) +ᵥ
        (s.restrict S hS).circumcenter) =
    (↑(n + 1) / ↑(n - 1)) • (Finset.centroid ℝ univ s.points -ᵥ s.circumcenter) +ᵥ s.circumcenter

Tactic:
← Simplex.centroid,

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
this : Nonempty ↥S
⊢ ↑((↑(n + 1) / ↑(n - 1)) • ((s.restrict S hS).centroid -ᵥ (s.restrict S hS).circumcenter) +ᵥ
        (s.restrict S hS).circumcenter) =
    (↑(n + 1) / ↑(n - 1)) • (Finset.centroid ℝ univ s.points -ᵥ s.circumcenter) +ᵥ s.circumcenter
Module: Mathlib.Geometry.Euclidean.Simplex

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)
⊢ ‖s.points i -ᵥ s.centroid‖ = ↑n * ‖s.centroid -ᵥ s.faceOppositeCentroid i‖

Tactic:
s.point_vsub_centroid_eq_smul_vsub i,

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)
⊢ ‖↑n • (s.centroid -ᵥ s.faceOppositeCentroid i)‖ = ↑n * ‖s.centroid -ᵥ s.faceOppositeCentroid i‖
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 p q : P
hp : p ∈ line[ℝ, a, b]
hq : dist a q = dist b q
m : P := midpoint ℝ a b
h1 : m -ᵥ p - (m -ᵥ a) = a -ᵥ p
h1' : m -ᵥ a - (m -ᵥ p) = p -ᵥ a
h2 : m -ᵥ q - (m -ᵥ p) = p -ᵥ q
h3 : m -ᵥ q - (m -ᵥ a) = a -ᵥ q
h : ∀ (r : P), b -ᵥ r = m -ᵥ r + (m -ᵥ a)
⊢ ‖m -ᵥ p - (m -ᵥ a)‖ * ‖b -ᵥ p‖ = |‖b -ᵥ q‖ ^ 2 - ‖m -ᵥ q - (m -ᵥ p)‖ ^ 2|

Tactic:
h,

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 p q : P
hp : p ∈ line[ℝ, a, b]
hq : dist a q = dist b q
m : P := midpoint ℝ a b
h1 : m -ᵥ p - (m -ᵥ a) = a -ᵥ p
h1' : m -ᵥ a - (m -ᵥ p) = p -ᵥ a
h2 : m -ᵥ q - (m -ᵥ p) = p -ᵥ q
h3 : m -ᵥ q - (m -ᵥ a) = a -ᵥ q
h : ∀ (r : P), b -ᵥ r = m -ᵥ r + (m -ᵥ a)
⊢ ‖m -ᵥ p - (m -ᵥ a)‖ * ‖m -ᵥ p + (m -ᵥ a)‖ = |‖b -ᵥ q‖ ^ 2 - ‖m -ᵥ q - (m -ᵥ p)‖ ^ 2|
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 p q : P
m : P := midpoint ℝ a b
hq : ‖m -ᵥ q - (m -ᵥ a)‖ = ‖m -ᵥ q + (m -ᵥ a)‖
h1 : m -ᵥ p - (m -ᵥ a) = a -ᵥ p
h1' : m -ᵥ a - (m -ᵥ p) = p -ᵥ a
h2 : m -ᵥ q - (m -ᵥ p) = p -ᵥ q
h3 : m -ᵥ q - (m -ᵥ a) = a -ᵥ q
h : ∀ (r : P), b -ᵥ r = m -ᵥ r + (m -ᵥ a)
r : ℝ
hr : r • (b -ᵥ a) = p -ᵥ a
⊢ ∃ k, m -ᵥ p = k • (m -ᵥ a)

Tactic:
h,

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 p q : P
m : P := midpoint ℝ a b
hq : ‖m -ᵥ q - (m -ᵥ a)‖ = ‖m -ᵥ q + (m -ᵥ a)‖
h1 : m -ᵥ p - (m -ᵥ a) = a -ᵥ p
h1' : m -ᵥ a - (m -ᵥ p) = p -ᵥ a
h2 : m -ᵥ q - (m -ᵥ p) = p -ᵥ q
h3 : m -ᵥ q - (m -ᵥ a) = a -ᵥ q
h : ∀ (r : P), b -ᵥ r = m -ᵥ r + (m -ᵥ a)
r : ℝ
hr : r • (m -ᵥ a + (m -ᵥ a)) = p -ᵥ a
⊢ ∃ k, m -ᵥ p = k • (m -ᵥ a)
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

Goal state before:
pp: case refine_1.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
p : P
hp : p ∈ s
v : V
p' : P
hp' : p' ∈ AffineSubspace.mk' p (ℝ ∙ v)
h : p' = s.secondInter p v
⊢ p' ∈ s

Tactic:
h,

Goal state after:
case refine_1.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
p : P
hp : p ∈ s
v : V
p' : P
hp' : p' ∈ AffineSubspace.mk' p (ℝ ∙ v)
h : p' = s.secondInter p v
⊢ s.secondInter p v ∈ s
Module: Mathlib.Geometry.Euclidean.Sphere.SecondInter

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 : Sphere P
p p' : P
hp : p ∈ s
hp' : dist p' s.center < s.radius
h : p' = s.secondInter p (p' -ᵥ p)
⊢ False

Tactic:
h,

Goal state after:
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 : Sphere P
p p' : P
hp : p ∈ s
hp' : dist (s.secondInter p (p' -ᵥ p)) s.center < s.radius
h : p' = s.secondInter p (p' -ᵥ p)
⊢ False
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
ho : OrthocentricSystem s
p : Fin 3 → P
hps : Set.range p ⊆ s
hpi : Function.Injective p
⊢ affineSpan ℝ (Set.range p) = affineSpan ℝ s

Tactic:
have ha := ho.affineIndependent hps hpi
  rcases ho with ⟨t, _, hts⟩
  have hs : affineSpan ℝ s = affineSpan ℝ (Set.range t.points) := by
    rw [hts, affineSpan_insert_eq_affineSpan ℝ t.orthocenter_mem_affineSpan]
  refine ext_of_direction_eq ?_
    ⟨p 0, mem_affineSpan ℝ (Set.mem_range_self _), mem_affineSpan ℝ (hps (Set.mem_range_self _))⟩
  have hfd : FiniteDimensional ℝ (affineSpan ℝ s).direction := by rw [hs]; infer_instance
  refine Submodule.eq_of_le_of_finrank_eq (direction_le (affineSpan_mono ℝ hps)) ?_
  rw [hs, direction_affineSpan, direction_affineSpan, ha.finrank_vectorSpan (Fintype.card_fin _),
    t.independent.finrank_vectorSpan (Fintype.card_fin _)]

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

Goal state before:
pp: case mpr
𝕜 : Type u_1
inst✝¹⁰ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁹ : NormedAddCommGroup E
inst✝⁸ : NormedSpace 𝕜 E
H : Type u_3
inst✝⁷ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁶ : TopologicalSpace M
inst✝⁵ : ChartedSpace H M
E' : Type u_5
inst✝⁴ : NormedAddCommGroup E'
inst✝³ : NormedSpace 𝕜 E'
H' : Type u_6
inst✝² : TopologicalSpace H'
N : Type u_7
inst✝¹ : TopologicalSpace N
inst✝ : ChartedSpace H' N
J : ModelWithCorners 𝕜 E' H'
p : M × N
aux : interior (range ↑I) ×ˢ interior (range ↑J) = interior (range ↑(I.prod J))
hp : p ∈ ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N
h : p.1 ∈ ModelWithCorners.interior M ∧ p.2 ∈ ModelWithCorners.interior N
⊢ (↑(extChartAt (I.prod J) p) p).1 ∈ interior (range ↑I) ∧ (↑(extChartAt (I.prod J) p) p).2 ∈ interior (range ↑J)

Tactic:
ModelWithCorners.interior

Goal state after:
case mpr
𝕜 : Type u_1
inst✝¹⁰ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁹ : NormedAddCommGroup E
inst✝⁸ : NormedSpace 𝕜 E
H : Type u_3
inst✝⁷ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁶ : TopologicalSpace M
inst✝⁵ : ChartedSpace H M
E' : Type u_5
inst✝⁴ : NormedAddCommGroup E'
inst✝³ : NormedSpace 𝕜 E'
H' : Type u_6
inst✝² : TopologicalSpace H'
N : Type u_7
inst✝¹ : TopologicalSpace N
inst✝ : ChartedSpace H' N
J : ModelWithCorners 𝕜 E' H'
p : M × N
aux : interior (range ↑I) ×ˢ interior (range ↑J) = interior (range ↑(I.prod J))
hp : p ∈ ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N
h : p.1 ∈ {x | I.IsInteriorPoint x} ∧ p.2 ∈ ModelWithCorners.interior N
⊢ (↑(extChartAt (I.prod J) p) p).1 ∈ interior (range ↑I) ∧ (↑(extChartAt (I.prod J) p) p).2 ∈ interior (range ↑J)
Module: Mathlib.Geometry.Manifold.IsManifold.InteriorBoundary

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁰ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁹ : NormedAddCommGroup E
inst✝⁸ : NormedSpace 𝕜 E
H : Type u_3
inst✝⁷ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁶ : TopologicalSpace M
inst✝⁵ : ChartedSpace H M
E' : Type u_5
inst✝⁴ : NormedAddCommGroup E'
inst✝³ : NormedSpace 𝕜 E'
H' : Type u_6
inst✝² : TopologicalSpace H'
N : Type u_7
inst✝¹ : TopologicalSpace N
inst✝ : ChartedSpace H' N
J : ModelWithCorners 𝕜 E' H'
h : ModelWithCorners.boundary (M × N) =
  (ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ :=
  Trans.trans
    (Trans.trans (Trans.trans rfl (Eq.symm compl_interior))
      (Eq.mpr
        (id (congrArg (fun _a ↦ _aᶜ = (ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N)ᶜ) interior_prod))
        (Eq.refl (ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N)ᶜ)))
    (Eq.mpr
      (id
        (congrArg (fun _a ↦ _a = (ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ)
          (compl_prod_eq_union (ModelWithCorners.interior M) (ModelWithCorners.interior N))))
      (Eq.refl ((ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ)))
⊢ ModelWithCorners.boundary (M × N) = univ.prod (ModelWithCorners.boundary N) ∪ (ModelWithCorners.boundary M).prod univ

Tactic:
h,

Goal state after:
𝕜 : Type u_1
inst✝¹⁰ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁹ : NormedAddCommGroup E
inst✝⁸ : NormedSpace 𝕜 E
H : Type u_3
inst✝⁷ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝⁶ : TopologicalSpace M
inst✝⁵ : ChartedSpace H M
E' : Type u_5
inst✝⁴ : NormedAddCommGroup E'
inst✝³ : NormedSpace 𝕜 E'
H' : Type u_6
inst✝² : TopologicalSpace H'
N : Type u_7
inst✝¹ : TopologicalSpace N
inst✝ : ChartedSpace H' N
J : ModelWithCorners 𝕜 E' H'
h : ModelWithCorners.boundary (M × N) =
  (ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ :=
  Trans.trans
    (Trans.trans (Trans.trans rfl (Eq.symm compl_interior))
      (Eq.mpr
        (id (congrArg (fun _a ↦ _aᶜ = (ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N)ᶜ) interior_prod))
        (Eq.refl (ModelWithCorners.interior M ×ˢ ModelWithCorners.interior N)ᶜ)))
    (Eq.mpr
      (id
        (congrArg (fun _a ↦ _a = (ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ)
          (compl_prod_eq_union (ModelWithCorners.interior M) (ModelWithCorners.interior N))))
      (Eq.refl ((ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ)))
⊢ (ModelWithCorners.interior M)ᶜ ×ˢ univ ∪ univ ×ˢ (ModelWithCorners.interior N)ᶜ =
    univ.prod (ModelWithCorners.boundary N) ∪ (ModelWithCorners.boundary M).prod univ