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

Goal state before:
pp: case h.right
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✝ : s.direction.HasOrthogonalProjection
ps : Set P
hnps : ps.Nonempty
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
t₃ : ℝ
cc₃' : P
hcc₃' : cc₃' ∈ s
hcc₃'' : cc₃ = t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc₃'
hcr₃' : ∃ r, ∀ p₁ ∈ ps, dist p₁ ↑((orthogonalProjection s) (t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc₃')) = r
⊢ { center := cc₃, radius := cr₃ } = { center := cc₂, radius := cr₂ }

Tactic:
orthogonalProjection_vadd_smul_vsub_orthogonalProjection _ _ hcc₃'

Goal state after:
case h.right
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✝ : s.direction.HasOrthogonalProjection
ps : Set P
hnps : ps.Nonempty
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
t₃ : ℝ
cc₃' : P
hcc₃' : cc₃' ∈ s
hcc₃'' : cc₃ = t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc₃'
hcr₃' : ∃ r, ∀ p₁ ∈ ps, dist p₁ ↑⟨cc₃', hcc₃'⟩ = r
⊢ { center := cc₃, radius := cr₃ } = { center := cc₂, radius := cr₂ }
Module: Mathlib.Geometry.Euclidean.Incenter

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
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:
simp [excenterWeightsUnnorm, h.symm]

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
s : AffineSubspace ℝ P
inst✝ : s.direction.HasOrthogonalProjection
ps : Set P
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
t₃ : ℝ
hcc₃' : cc ∈ s
hcc₃'' : cc₃ = t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
hcr₃' : ∀ p₁ ∈ ps, dist p₁ ↑⟨cc, hcc₃'⟩ = cr
p0 : P
hp0 : p0 ∈ ps
h' : ↑⟨cc, hcc₃'⟩ = cc
⊢ dist p0 cc * dist p0 cc +
      dist (t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc) cc *
        dist (t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc) cc =
    cr * cr + t₃ * y * (t₃ * y)

Tactic:
dist_of_mem_subset_mk_sphere hp0 hcr,

Goal state after:
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
s : AffineSubspace ℝ P
inst✝ : s.direction.HasOrthogonalProjection
ps : Set P
p : P
hps : ps ⊆ ↑s
hp : p ∉ s
this : Nonempty ↥s
cc : P
cr : ℝ
hcccru : ∀ (y : Sphere P), y.center ∈ s ∧ ps ⊆ Metric.sphere y.center y.radius → y = { center := cc, radius := cr }
hcc : cc ∈ s
hcr : ps ⊆ Metric.sphere cc cr
x : ℝ := dist cc ↑((orthogonalProjection s) p)
y : ℝ := dist p ↑((orthogonalProjection s) p)
hy0 : y ≠ 0
ycc₂ : ℝ := (x * x + y * y - cr * cr) / (2 * y)
cc₂ : P := (ycc₂ / y) • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
cr₂ : ℝ := √(cr * cr + ycc₂ * ycc₂)
hpo : p = 1 • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ ↑((orthogonalProjection s) p)
cc₃ : P
cr₃ : ℝ
hcc₃ : cc₃ ∈ affineSpan ℝ (insert p ↑s)
hcr₃ : insert p ps ⊆ Metric.sphere cc₃ cr₃
t₃ : ℝ
hcc₃' : cc ∈ s
hcc₃'' : cc₃ = t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc
hcr₃' : ∀ p₁ ∈ ps, dist p₁ ↑⟨cc, hcc₃'⟩ = cr
p0 : P
hp0 : p0 ∈ ps
h' : ↑⟨cc, hcc₃'⟩ = cc
⊢ cr * cr +
      dist (t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc) cc *
        dist (t₃ • (p -ᵥ ↑((orthogonalProjection s) p)) +ᵥ cc) cc =
    cr * cr + t₃ * y * (t₃ * y)
Module: Mathlib.Geometry.Euclidean.Triangle

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : x ≠ 0
hxy : x - y ≠ 0
⊢ Real.sin (angle x y) / ‖x - y‖ = Real.sin (angle y (x - y)) / ‖x‖

Tactic:
simp [field, sin_angle_mul_norm_eq_sin_angle_mul_norm x y]

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

Goal state before:
pp: case intro.succ.succ
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
ι : Type u_3
hne : Nonempty ι
inst✝ : Finite ι
p : ι → P
ha : AffineIndependent ℝ p
val✝ : Fintype ι
m : ℕ
hm :
  ∀ {ι : Type u_3} [hne : Nonempty ι] [Finite ι] {p : ι → P},
    AffineIndependent ℝ p →
      ∀ (val : Fintype ι),
        Fintype.card ι = m + 1 →
          ∃! cs, cs.center ∈ affineSpan ℝ (Set.range p) ∧ Set.range p ⊆ Metric.sphere cs.center cs.radius
hn : Fintype.card ι = m + 1 + 1
⊢ ∃! cs, cs.center ∈ affineSpan ℝ (Set.range p) ∧ Set.range p ⊆ Metric.sphere cs.center cs.radius

Tactic:
· have i := hne.some
      let ι2 := { x // x ≠ i }
      classical
      have hc : Fintype.card ι2 = m + 1 := by
        rw [Fintype.card_of_subtype {x | x ≠ i}]
        · rw [Finset.filter_not, Finset.filter_eq' _ i, if_pos (Finset.mem_univ _),
            Finset.card_sdiff, Finset.card_univ, hn]
          simp
        · simp
      have : Nonempty ι2 := Fintype.card_pos_iff.1 (hc.symm ▸ Nat.zero_lt_succ _)
      have ha2 : AffineIndependent ℝ fun i2 : ι2 => p i2 := ha.subtype _
      replace hm := hm ha2 _ hc
      have hr : Set.range p = insert (p i) (Set.range fun i2 : ι2 => p i2) := by
        change _ = insert _ (Set.range fun i2 : { x | x ≠ i } => p i2)
        rw [← Set.image_eq_range, ← Set.image_univ, ← Set.image_insert_eq]
        congr with j
        simp [Classical.em]
      rw [hr, ← affineSpan_insert_affineSpan]
      refine existsUnique_dist_eq_of_insert (Set.range_nonempty _) (subset_affineSpan ℝ _) ?_ hm
      convert! ha.notMem_affineSpan_sdiff i Set.univ
      change (Set.range fun i2 : { x | x ≠ i } => p i2) = _
      rw [← Set.image_eq_range]
      congr 1 with j
      simp

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
H : |⟪x, NormedSpace.normalize (ortho y x)⟫| = Real.sin (angle x y)
⊢ 0 ≤ ⟪x, NormedSpace.normalize (ortho y x)⟫

Tactic:
rw [NormedSpace.normalize, real_inner_smul_right]

Goal state after:
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y : V
hx : ‖x‖ = 1
hy : ‖y‖ = 1
H : |⟪x, NormedSpace.normalize (ortho y x)⟫| = Real.sin (angle x y)
⊢ 0 ≤ ‖ortho y x‖⁻¹ * ⟪x, ortho y x⟫
Module: Mathlib.Geometry.Euclidean.Incenter

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i j : Fin (n + 1)
hne : i ≠ j
r : ℝ
hr : r ∈ Set.Icc 0 1
t : ℝ
ht : t ∈ Set.Icc 0 1
⊢ (s.signedInfDist j) ((AffineMap.lineMap (s.excenter signs) (s.touchpoint signs i)) t) ≠ 0

Tactic:
intro h0

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
n : ℕ
inst✝ : NeZero n
s : Simplex ℝ P n
signs : Finset (Fin (n + 1))
h : s.ExcenterExists signs
i j : Fin (n + 1)
hne : i ≠ j
r : ℝ
hr : r ∈ Set.Icc 0 1
t : ℝ
ht : t ∈ Set.Icc 0 1
h0 : (s.signedInfDist j) ((AffineMap.lineMap (s.excenter signs) (s.touchpoint signs i)) t) = 0
⊢ False
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
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
⊢ Real.sin (angle x z) ≠ 0

Tactic:
grind [sin_eq_zero_iff_angle_eq_zero_or_angle_eq_pi]

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 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)⟫
⊢ Real.sin (angle x y) * Real.sin (angle y z) ≠ 0

Tactic:
grind [sin_eq_zero_iff_angle_eq_zero_or_angle_eq_pi]

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 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
⊢ Real.sin (angle x z) ≠ 0

Tactic:
grind [sin_eq_zero_iff_angle_eq_zero_or_angle_eq_pi]

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

Goal state before:
pp: V₁ : Type u_2
V₂ : Type u_3
P₁ : Type u_4
P₂ : Type u_5
inst✝⁷ : NormedAddCommGroup V₁
inst✝⁶ : NormedAddCommGroup V₂
inst✝⁵ : InnerProductSpace ℝ V₁
inst✝⁴ : InnerProductSpace ℝ V₂
inst✝³ : MetricSpace P₁
inst✝² : MetricSpace P₂
inst✝¹ : NormedAddTorsor V₁ P₁
inst✝ : NormedAddTorsor V₂ P₂
a b c : P₁
a' b' c' : P₂
h : ¬Collinear ℝ {a, b, c}
ha₁ : ∠ a b c = ∠ a' b' c'
hd : dist b c = dist b' c'
ha₂ : ∠ b c a = ∠ b' c' a'
h' : ¬Collinear ℝ {a', b', c'}
ha₃' : ∠ c' a' b' + ∠ a' b' c' + ∠ b' c' a' = Real.pi
ha₃ : ∠ c a b = ∠ c' a' b'
h_bac : ¬Collinear ℝ {b, a, c}
h_bac' : ¬Collinear ℝ {b', a', c'}
⊢ dist c b * Real.sin (∠ a c b) / Real.sin (∠ b a c) = dist c' b' * Real.sin (∠ a' c' b') / Real.sin (∠ b' a' c')

Tactic:
dist_comm c b,

Goal state after:
V₁ : Type u_2
V₂ : Type u_3
P₁ : Type u_4
P₂ : Type u_5
inst✝⁷ : NormedAddCommGroup V₁
inst✝⁶ : NormedAddCommGroup V₂
inst✝⁵ : InnerProductSpace ℝ V₁
inst✝⁴ : InnerProductSpace ℝ V₂
inst✝³ : MetricSpace P₁
inst✝² : MetricSpace P₂
inst✝¹ : NormedAddTorsor V₁ P₁
inst✝ : NormedAddTorsor V₂ P₂
a b c : P₁
a' b' c' : P₂
h : ¬Collinear ℝ {a, b, c}
ha₁ : ∠ a b c = ∠ a' b' c'
hd : dist b c = dist b' c'
ha₂ : ∠ b c a = ∠ b' c' a'
h' : ¬Collinear ℝ {a', b', c'}
ha₃' : ∠ c' a' b' + ∠ a' b' c' + ∠ b' c' a' = Real.pi
ha₃ : ∠ c a b = ∠ c' a' b'
h_bac : ¬Collinear ℝ {b, a, c}
h_bac' : ¬Collinear ℝ {b', a', c'}
⊢ dist b c * Real.sin (∠ a c b) / Real.sin (∠ b a c) = dist c' b' * Real.sin (∠ a' c' b') / Real.sin (∠ b' a' c')
Module: Mathlib.Geometry.Euclidean.Inversion.ImageHyperplane

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

Tactic:
simp [inversion_mem_perpBisector_inversion_iff hR hx hy, hx]

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

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

Tactic:
have hz : ⟪p -ᵥ orthogonalProjection span_s p, p -ᵥ orthogonalProjection span_s p⟫ ≠ 0 := by
      simpa only [Ne, vsub_eq_zero_iff_eq, inner_self_eq_zero] using! hp

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
p p₁ p₂ : P
r : ℝ
h₁ : ∀ (i : Fin (n + 1)), dist (s.points i) p₁ = r
h₂ : ∀ (i : Fin (n + 1)), dist (s.points i) p₂ = r
span_s : AffineSubspace ℝ P := affineSpan ℝ (Set.range s.points)
h₁' : ↑(s.orthogonalProjectionSpan p₁) = s.circumcenter
h₂' : ↑(s.orthogonalProjectionSpan p₂) = s.circumcenter
r₁ r₂ : ℝ
hp₁o : ↑(s.orthogonalProjectionSpan p₁) ∈ affineSpan ℝ (Set.range s.points)
hp₁ : p₁ = r₁ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
hp₂o : ↑(s.orthogonalProjectionSpan p₂) ∈ affineSpan ℝ (Set.range s.points)
hp₂ : p₂ = r₂ • (p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)) +ᵥ s.circumcenter
h : s.points 0 ∈ span_s
hd₁ :
  r₁ * r₁ *
      ⟪p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p),
        p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)⟫ =
    r₂ * r₂ *
      ⟪p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p),
        p -ᵥ ↑((orthogonalProjection (affineSpan ℝ (Set.range s.points))) p)⟫
hd₂ : dist p₂ s.circumcenter * dist p₂ s.circumcenter = r * r - s.circumradius * s.circumradius
hp : ¬p = ↑(s.orthogonalProjectionSpan p)
hz : ⟪p -ᵥ ↑((orthogonalProjection span_s) p), p -ᵥ ↑((orthogonalProjection span_s) p)⟫ ≠ 0
⊢ p₁ = p₂ ∨ p₁ = (reflection (affineSpan ℝ (Set.range s.points))) p₂
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} i₂) (t.points i₃)

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

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
s : Simplex ℝ P n
⊢ ((↑n + 1) / ↑n) • (s.centroid -ᵥ s.circumcenter) +ᵥ s.circumcenter ∈ affineSpan ℝ (Set.range s.points)

Tactic:
refine AffineSubspace.vadd_mem_of_mem_direction ?_ s.circumcenter_mem_affineSpan

Goal state after:
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
n : ℕ
s : Simplex ℝ P n
⊢ ((↑n + 1) / ↑n) • (s.centroid -ᵥ s.circumcenter) ∈ (affineSpan ℝ (Set.range s.points)).direction
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.faceOppositeCentroid i‖ = (↑n + 1) * ‖s.centroid -ᵥ s.faceOppositeCentroid i‖

Tactic:
s.point_vsub_faceOppositeCentroid_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 + 1) • (s.centroid -ᵥ s.faceOppositeCentroid i)‖ = (↑n + 1) * ‖s.centroid -ᵥ s.faceOppositeCentroid i‖
Module: Mathlib.Geometry.Euclidean.Sphere.Power

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
x y z : V
h₃ : ‖z - y‖ = ‖z + y‖
r : ℝ
hr : x = r • y
hzy : ⟪z, y⟫ = 0
hzx : ⟪z, x⟫ = 0
⊢ |r ^ 2 * ‖y‖ ^ 2 - ‖y‖ ^ 2| = |‖x‖ ^ 2 - ‖y‖ ^ 2|

Tactic:
simp [hr, norm_smul, mul_pow, sq_abs]

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}
this : AffineIndependent ℝ ![p₁, p, p₃]
⊢ ¬Collinear ℝ {p₁, p₂, p₃}

Tactic:
rw [← affineIndependent_iff_not_collinear_set]

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]
⊢ AffineIndependent ℝ ![p₁, p₂, p₃]
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
t : Triangle ℝ P
i : Fin 3
⊢ dist (t.points i) (Simplex.faceOppositeCentroid t i) =
    3 * dist (Simplex.centroid t) (Simplex.faceOppositeCentroid t i)

Tactic:
rw [Affine.Simplex.dist_point_faceOppositeCentroid]

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
i : Fin 3
⊢ (↑2 + 1) * dist (Simplex.centroid t) (Simplex.faceOppositeCentroid t i) =
    3 * dist (Simplex.centroid t) (Simplex.faceOppositeCentroid t i)
Module: Mathlib.Geometry.Manifold.Algebra.SmoothFunctions

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁶ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹⁵ : NormedAddCommGroup E
inst✝¹⁴ : NormedSpace 𝕜 E
E' : Type u_3
inst✝¹³ : NormedAddCommGroup E'
inst✝¹² : NormedSpace 𝕜 E'
H : Type u_4
inst✝¹¹ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
H' : Type u_5
inst✝¹⁰ : TopologicalSpace H'
I' : ModelWithCorners 𝕜 E' H'
N : Type u_6
inst✝⁹ : TopologicalSpace N
inst✝⁸ : ChartedSpace H N
E'' : Type u_7
inst✝⁷ : NormedAddCommGroup E''
inst✝⁶ : NormedSpace 𝕜 E''
H'' : Type u_8
inst✝⁵ : TopologicalSpace H''
I'' : ModelWithCorners 𝕜 E'' H''
N' : Type u_9
inst✝⁴ : TopologicalSpace N'
inst✝³ : ChartedSpace H'' N'
n : ℕ∞ω
A : Type u_10
inst✝² : NormedRing A
inst✝¹ : NormedAlgebra 𝕜 A
inst✝ : ContMDiffRing 𝓘(𝕜, A) n A
c : 𝕜
f : C^n⟮I, N; 𝓘(𝕜, A), A⟯
⊢ c • f = C c * f

Tactic:
by ext x; exact Algebra.smul_def' _ _

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

Goal state before:
pp: 𝕜 : Type u_1
inst✝⁵ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝⁴ : NormedAddCommGroup E
inst✝³ : NormedSpace 𝕜 E
H : Type u_3
inst✝² : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹ : TopologicalSpace M
inst✝ : ChartedSpace H M
x : M
⊢ I.IsInteriorPoint x ∨ I.IsBoundaryPoint x

Tactic:
by
  rw [IsInteriorPoint, or_iff_not_imp_left, I.isBoundaryPoint_iff, ← closure_sdiff_interior,
    I.isClosed_range.closure_eq, mem_sdiff]
  exact fun h ↦ ⟨mem_range_self _, h⟩

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

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Set P
t t₀ : Triangle ℝ P
ht : Set.range t.points ⊆ insert t₀.orthocenter (Set.range t₀.points)
ht₀o : t₀.orthocenter ∉ Set.range t₀.points
ht₀s : s = insert t₀.orthocenter (Set.range t₀.points)
i₁ i₂ i₃ j₂ j₃ : Fin 3
h₁₂ : i₁ ≠ i₂
h₁₃ : i₁ ≠ i₃
h₂₃ : i₂ ≠ i₃
h₁₂₃ : ∀ (i : Fin 3), i = i₁ ∨ i = i₂ ∨ i = i₃
h₁ : t.points i₁ = t₀.orthocenter
hj₂₃ : j₂ ≠ j₃
h₂ : t₀.points j₂ = t.points i₂
h₃ : t₀.points j₃ = t.points i₃
j₁ : Fin 3
hj₁₂ : j₁ ≠ j₂
hj₁₃ : j₁ ≠ j₃
hj₁₂₃ : ∀ (j : Fin 3), j = j₁ ∨ j = j₂ ∨ j = j₃
h : t₀.points j₁ = t.orthocenter
hui : Set.univ = {i₁, i₂, i₃}
x : Fin 3
⊢ x ∈ Set.univ ↔ x ∈ {j₁, j₂, j₃}

Tactic:
simpa using hj₁₂₃ x

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

Goal state before:
pp: case refine_1
𝕜 : Type u_1
B : Type u_2
F : Type u_4
E : B → Type u_6
inst✝¹³ : TopologicalSpace B
inst✝¹² : TopologicalSpace (TotalSpace F E)
inst✝¹¹ : (x : B) → TopologicalSpace (E x)
inst✝¹⁰ : NormedAddCommGroup F
inst✝⁹ : NontriviallyNormedField 𝕜
inst✝⁸ : NormedSpace 𝕜 F
inst✝⁷ : FiberBundle F E
inst✝⁶ : (x : B) → AddCommGroup (E x)
inst✝⁵ : (x : B) → Module 𝕜 (E x)
inst✝⁴ : VectorBundle 𝕜 F E
HB : Type u_7
inst✝³ : TopologicalSpace HB
inst✝² : ChartedSpace HB B
EB : Type u_8
inst✝¹ : NormedAddCommGroup EB
inst✝ : NormedSpace 𝕜 EB
I : ModelWithCorners 𝕜 EB HB
s t : (x : B) → E x
u : Set B
x₀ : B
e : Trivialization F TotalSpace.proj := trivializationAt F E x₀
hs : (MDiffAt[u] fun b ↦ (↑e ⟨b, s b⟩).2) x₀
ht : (MDiffAt[u] fun b ↦ (↑e ⟨b, t b⟩).2) x₀
⊢ (fun b ↦ (↑e ⟨b, (s + t) b⟩).2) =ᶠ[𝓝[u] x₀] (fun b ↦ (↑e ⟨b, s b⟩).2) + fun b ↦ (↑e ⟨b, t b⟩).2

Tactic:
apply eventually_of_mem (U := e.baseSet)
    · exact mem_nhdsWithin_of_mem_nhds <|
        (e.open_baseSet.mem_nhds <| mem_baseSet_trivializationAt F E x₀)
    · exact fun x hx ↦ (e.linear 𝕜 hx).1 ..

Goal state after: