mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.FieldTheory.KummerExtension

Goal state before:
pp: K : Type u
inst✝³ : Field K
n : ℕ
hζ : (primitiveRoots n K).Nonempty
a : K
H : Irreducible (X ^ n - C a)
L : Type u_1
inst✝² : Field L
inst✝¹ : Algebra K L
inst✝ : IsSplittingField K L (X ^ n - C a)
α : L
hα : α ^ n = (algebraMap K L) a
⊢ (liftAlgHom (X ^ n - C a) (Algebra.ofId K L) α ⋯) (root (X ^ n - C a)) = α

Tactic:
liftAlgHom_root

Goal state after:
K : Type u
inst✝³ : Field K
n : ℕ
hζ : (primitiveRoots n K).Nonempty
a : K
H : Irreducible (X ^ n - C a)
L : Type u_1
inst✝² : Field L
inst✝¹ : Algebra K L
inst✝ : IsSplittingField K L (X ^ n - C a)
α : L
hα : α ^ n = (algebraMap K L) a
⊢ α = α
Module: Mathlib.RingTheory.LinearDisjoint

Goal state before:
pp: R : Type u
inst✝⁸ : CommRing R
A : Type v
inst✝⁷ : CommRing A
B : Type w
inst✝⁶ : CommRing B
inst✝⁵ : Algebra R A
inst✝⁴ : Algebra R B
inst✝³ : Flat R A
inst✝² : Flat R B
inst✝¹ : Algebra.Transcendental R A
inst✝ : Algebra.Transcendental R B
H : IsField (A ⊗[R] B)
this✝³ : Field (A ⊗[R] B) := H.toField
a : A
b : B
ha : Function.Injective ⇑(algebraMap R A)
hb : Function.Injective ⇑(algebraMap R B)
fa : A →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeLeft
fb : B →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeRight
hfa : Function.Injective ⇑fa
hfb : Function.Injective ⇑fb
this✝² : IsDomain A
this✝¹ : IsDomain B
this✝ : IsDomain R
this : Flat R ↥(toSubmodule fa.range)
key1 : Module.rank R ↥(fa.range ⊓ fb.range) ≤ 1
ga : R[X] →ₐ[R] A := aeval a
gb : R[X] →ₐ[R] B := aeval b
gab : R[X] →ₐ[R] A ⊗[R] B := fa.comp ga
hta : Function.Injective ⇑ga
htb : Function.Injective ⇑gb
htab : Function.Injective ⇑gab
algInst✝¹ : Algebra R[X] A := ga.toAlgebra
algInst✝ : Algebra R[X] B := gb.toAlgebra
f : A ⊗[R] B →ₐ[R] A ⊗[R[X]] B := Algebra.TensorProduct.mapOfCompatibleSMul R[X] R R A B
⊢ False

Tactic:
have := Algebra.TensorProduct.nontrivial_of_algebraMap_injective_of_isDomain R[X] A B hta htb

Goal state after:
R : Type u
inst✝⁸ : CommRing R
A : Type v
inst✝⁷ : CommRing A
B : Type w
inst✝⁶ : CommRing B
inst✝⁵ : Algebra R A
inst✝⁴ : Algebra R B
inst✝³ : Flat R A
inst✝² : Flat R B
inst✝¹ : Algebra.Transcendental R A
inst✝ : Algebra.Transcendental R B
H : IsField (A ⊗[R] B)
this✝⁴ : Field (A ⊗[R] B) := H.toField
a : A
b : B
ha : Function.Injective ⇑(algebraMap R A)
hb : Function.Injective ⇑(algebraMap R B)
fa : A →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeLeft
fb : B →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeRight
hfa : Function.Injective ⇑fa
hfb : Function.Injective ⇑fb
this✝³ : IsDomain A
this✝² : IsDomain B
this✝¹ : IsDomain R
this✝ : Flat R ↥(toSubmodule fa.range)
key1 : Module.rank R ↥(fa.range ⊓ fb.range) ≤ 1
ga : R[X] →ₐ[R] A := aeval a
gb : R[X] →ₐ[R] B := aeval b
gab : R[X] →ₐ[R] A ⊗[R] B := fa.comp ga
hta : Function.Injective ⇑ga
htb : Function.Injective ⇑gb
htab : Function.Injective ⇑gab
algInst✝¹ : Algebra R[X] A := ga.toAlgebra
algInst✝ : Algebra R[X] B := gb.toAlgebra
f : A ⊗[R] B →ₐ[R] A ⊗[R[X]] B := Algebra.TensorProduct.mapOfCompatibleSMul R[X] R R A B
this : Nontrivial (A ⊗[R[X]] B)
⊢ False
Module: Mathlib.RingTheory.LinearDisjoint

Goal state before:
pp: R : Type u
inst✝⁸ : CommRing R
A : Type v
inst✝⁷ : CommRing A
B : Type w
inst✝⁶ : CommRing B
inst✝⁵ : Algebra R A
inst✝⁴ : Algebra R B
inst✝³ : Flat R A
inst✝² : Flat R B
inst✝¹ : Algebra.Transcendental R A
inst✝ : Algebra.Transcendental R B
H : IsField (A ⊗[R] B)
this✝⁴ : Field (A ⊗[R] B) := H.toField
a : A
b : B
ha : Function.Injective ⇑(algebraMap R A)
hb : Function.Injective ⇑(algebraMap R B)
fa : A →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeLeft
fb : B →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeRight
hfa : Function.Injective ⇑fa
hfb : Function.Injective ⇑fb
this✝³ : IsDomain A
this✝² : IsDomain B
this✝¹ : IsDomain R
this✝ : Flat R ↥(toSubmodule fa.range)
key1 : Module.rank R ↥(fa.range ⊓ fb.range) ≤ 1
ga : R[X] →ₐ[R] A := aeval a
gb : R[X] →ₐ[R] B := aeval b
gab : R[X] →ₐ[R] A ⊗[R] B := fa.comp ga
hta : Function.Injective ⇑ga
htb : Function.Injective ⇑gb
htab : Function.Injective ⇑gab
algInst✝¹ : Algebra R[X] A := ga.toAlgebra
algInst✝ : Algebra R[X] B := gb.toAlgebra
f : A ⊗[R] B →ₐ[R] A ⊗[R[X]] B := Algebra.TensorProduct.mapOfCompatibleSMul R[X] R R A B
this : Nontrivial (A ⊗[R[X]] B)
hf : Function.Injective ⇑f
⊢ R[a ⊗ₜ[R] 1] ≤ fa.range ⊓ fb.range

Tactic:
simp_rw [Algebra.adjoin_le_iff, Set.singleton_subset_iff, Algebra.coe_inf, Set.mem_inter_iff,
      AlgHom.coe_range, Set.mem_range]

Goal state after:
R : Type u
inst✝⁸ : CommRing R
A : Type v
inst✝⁷ : CommRing A
B : Type w
inst✝⁶ : CommRing B
inst✝⁵ : Algebra R A
inst✝⁴ : Algebra R B
inst✝³ : Flat R A
inst✝² : Flat R B
inst✝¹ : Algebra.Transcendental R A
inst✝ : Algebra.Transcendental R B
H : IsField (A ⊗[R] B)
this✝⁴ : Field (A ⊗[R] B) := H.toField
a : A
b : B
ha : Function.Injective ⇑(algebraMap R A)
hb : Function.Injective ⇑(algebraMap R B)
fa : A →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeLeft
fb : B →ₐ[R] A ⊗[R] B := Algebra.TensorProduct.includeRight
hfa : Function.Injective ⇑fa
hfb : Function.Injective ⇑fb
this✝³ : IsDomain A
this✝² : IsDomain B
this✝¹ : IsDomain R
this✝ : Flat R ↥(toSubmodule fa.range)
key1 : Module.rank R ↥(fa.range ⊓ fb.range) ≤ 1
ga : R[X] →ₐ[R] A := aeval a
gb : R[X] →ₐ[R] B := aeval b
gab : R[X] →ₐ[R] A ⊗[R] B := fa.comp ga
hta : Function.Injective ⇑ga
htb : Function.Injective ⇑gb
htab : Function.Injective ⇑gab
algInst✝¹ : Algebra R[X] A := ga.toAlgebra
algInst✝ : Algebra R[X] B := gb.toAlgebra
f : A ⊗[R] B →ₐ[R] A ⊗[R[X]] B := Algebra.TensorProduct.mapOfCompatibleSMul R[X] R R A B
this : Nontrivial (A ⊗[R[X]] B)
hf : Function.Injective ⇑f
⊢ (∃ y, fa y = a ⊗ₜ[R] 1) ∧ ∃ y, fb y = a ⊗ₜ[R] 1
Module: Mathlib.FieldTheory.LinearDisjoint

Goal state before:
pp: F : Type u
E : Type v
inst✝⁵ : Field F
inst✝⁴ : Field E
inst✝³ : Algebra F E
A B : IntermediateField F E
inst✝² : IsGalois F ↥A
inst✝¹ : FiniteDimensional F ↥A
inst✝ : FiniteDimensional F ↥B
h : A ⊓ B = ⊥
C : IntermediateField F E := A ⊔ B
A' : IntermediateField F ↥C := restrict ⋯
B' : IntermediateField F ↥C := restrict ⋯
hA : IntermediateField.map C.val A' = A
hB : IntermediateField.map C.val B' = B
⊢ A'.LinearDisjoint ↥B'

Tactic:
have h₁ : A' ⊔ B' = ⊤ := by
    rw [← lift_inj, lift_top, lift_sup, lift_restrict le_sup_left, lift_restrict le_sup_right]

Goal state after:
F : Type u
E : Type v
inst✝⁵ : Field F
inst✝⁴ : Field E
inst✝³ : Algebra F E
A B : IntermediateField F E
inst✝² : IsGalois F ↥A
inst✝¹ : FiniteDimensional F ↥A
inst✝ : FiniteDimensional F ↥B
h : A ⊓ B = ⊥
C : IntermediateField F E := A ⊔ B
A' : IntermediateField F ↥C := restrict ⋯
B' : IntermediateField F ↥C := restrict ⋯
hA : IntermediateField.map C.val A' = A
hB : IntermediateField.map C.val B' = B
h₁ : A' ⊔ B' = ⊤
⊢ A'.LinearDisjoint ↥B'
Module: Mathlib.FieldTheory.PurelyInseparable.PerfectClosure

Goal state before:
pp: case refine_1
F : Type u
E : Type v
inst✝⁴ : Field F
inst✝³ : Field E
inst✝² : Algebra F E
S : Set E
inst✝¹ : Algebra.IsSeparable F ↥(adjoin F S)
q : ℕ
inst✝ : ExpChar F q
n : ℕ
M : IntermediateField F E := adjoin F ((fun x ↦ x ^ q ^ n) '' S)
this✝¹ : ExpChar (↥M) q
x : E
hx : x ∈ S
this✝ : Algebra.IsSeparable ↥M ↥(↥M)⟮x⟯
this : IsPurelyInseparable ↥M ↥(↥M)⟮x⟯
hx' : x ∈ (↥M)⟮x⟯
⊢ x ∈ ↑M

Tactic:
rw [M⟮x⟯.eq_bot_of_isPurelyInseparable_of_isSeparable, mem_bot] at hx'

Goal state after:
case refine_1
F : Type u
E : Type v
inst✝⁴ : Field F
inst✝³ : Field E
inst✝² : Algebra F E
S : Set E
inst✝¹ : Algebra.IsSeparable F ↥(adjoin F S)
q : ℕ
inst✝ : ExpChar F q
n : ℕ
M : IntermediateField F E := adjoin F ((fun x ↦ x ^ q ^ n) '' S)
this✝¹ : ExpChar (↥M) q
x : E
hx : x ∈ S
this✝ : Algebra.IsSeparable ↥M ↥(↥M)⟮x⟯
this : IsPurelyInseparable ↥M ↥(↥M)⟮x⟯
hx' : x ∈ Set.range ⇑(algebraMap (↥M) E)
⊢ x ∈ ↑M
Module: Mathlib.FieldTheory.RatFunc.IntermediateField

Goal state before:
pp: case pos
K : Type u_1
inst✝ : Field K
f : K⟮X⟯
hf : ∃ c, f = C c
⊢ Module.finrank (↥K⟮f⟯) K⟮X⟯ = max f.num.natDegree f.denom.natDegree

pp: case neg
K : Type u_1
inst✝ : Field K
f : K⟮X⟯
hf : ¬∃ c, f = C c
⊢ Module.finrank (↥K⟮f⟯) K⟮X⟯ = max f.num.natDegree f.denom.natDegree

Tactic:
· obtain ⟨c, rfl⟩ := hf
    rw [adjoin_simple_eq_bot_iff.mpr (show C c ∈ ⊥ from ⟨c, rfl⟩), finrank_bot',
      Module.finrank_of_not_finite fun H ↦ Algebra.transcendental_iff_not_isAlgebraic.mp
      transcendental <| Algebra.IsAlgebraic.of_finite K K⟮X⟯]
    simp

Goal state after:
case neg
K : Type u_1
inst✝ : Field K
f : K⟮X⟯
hf : ¬∃ c, f = C c
⊢ Module.finrank (↥K⟮f⟯) K⟮X⟯ = max f.num.natDegree f.denom.natDegree
Module: Mathlib.FieldTheory.Relrank

Goal state before:
pp: E : Type v
inst✝¹ : Field E
L : Type w
inst✝ : Field L
A : Subfield E
f : L →+* E
⊢ finrank (↥(comap f A)) L = A.relfinrank f.fieldRange

Tactic:
simpa using! congr(toNat $(lift_rank_comap A f))

Goal state after:
Module: Mathlib.Geometry.Convex.Cone.Face.Basic

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝⁴ : Semiring R
inst✝³ : PartialOrder R
inst✝² : IsOrderedRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
C₁ C₂ F₁ F₂ : PointedCone R M
h₁ : F₁.IsFaceOf C₁
h₂ : F₂.IsFaceOf C₂
⊢ (F₁ ⊓ F₂).IsFaceOf (C₁ ⊓ C₂)

Tactic:
use le_inf_iff.mpr ⟨Set.inter_subset_left.trans h₁.le, Set.inter_subset_right.trans h₂.le⟩
  simp only [mem_inf, and_imp]
  refine fun xc₁ xc₂ yc₁ yc₂ a0 hz₁ hz₂ ↦ ⟨?_, ?_⟩
  · exact h₁.mem_of_smul_add_mem xc₁ yc₁ a0 hz₁
  · exact h₂.mem_of_smul_add_mem xc₂ yc₂ a0 hz₂

Goal state after:
Module: Mathlib.FieldTheory.RatFunc.Luroth

Goal state before:
pp: K : Type u_1
inst✝ : Field K
E : IntermediateField K K⟮X⟯
h : E ≠ ⊥
this :
  (algebraMap K[X] K⟮X⟯) ((Φ E).coeff (generatorIndex h) * g E) =
    (algebraMap K[X] K⟮X⟯) (c E).num * (algebraMap K[X] K⟮X⟯) (generator E).num
⊢ (f E).natDegree ≤ ((Φ E).coeff (generatorIndex h)).natDegree

Tactic:
← map_mul

Goal state after:
K : Type u_1
inst✝ : Field K
E : IntermediateField K K⟮X⟯
h : E ≠ ⊥
this :
  (algebraMap K[X] K⟮X⟯) ((Φ E).coeff (generatorIndex h) * g E) = (algebraMap K[X] K⟮X⟯) ((c E).num * (generator E).num)
⊢ (f E).natDegree ≤ ((Φ E).coeff (generatorIndex h)).natDegree
Module: Mathlib.FieldTheory.Relrank

Goal state before:
pp: F : Type u
E : Type v
inst✝⁴ : Field F
inst✝³ : Field E
inst✝² : Algebra F E
L : Type w
inst✝¹ : Field L
inst✝ : Algebra F L
A : IntermediateField F E
f : L →ₐ[F] E
⊢ finrank (↥(comap f A)) L = A.relfinrank f.fieldRange

Tactic:
simpa using! congr(toNat $(lift_rank_comap A f))

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Rotation

Goal state before:
pp: case «1»
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
θ : Real.Angle
x : V
hx : x ≠ 0
⊢ ↑(o.rotation θ).toLinearEquiv ((o.basisRightAngleRotation x hx) ((fun i ↦ i) ⟨1, ⋯⟩)) =
    ((Matrix.toLin (o.basisRightAngleRotation x hx) (o.basisRightAngleRotation x hx)) !![θ.cos, -θ.sin; θ.sin, θ.cos])
      ((o.basisRightAngleRotation x hx) ((fun i ↦ i) ⟨1, ⋯⟩))

Tactic:
rw [Matrix.toLin_self]
    simp [rotation_apply, Fin.sum_univ_succ, add_comm]

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Rotation

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
hx : x ≠ 0
θ : Real.Angle
⊢ (o.rotation θ) x = x ↔ θ = 0

Tactic:
constructor
  · intro h
    rw [eq_comm]
    simpa [hx, h] using o.oangle_rotation_right hx hx θ
  · intro h
    simp [h]

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

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
p₁ p₂ p₃ : P
hp₁p₂ : p₂ -ᵥ p₁ ≠ 0
r : ℝ
hr : r < 0
hpr : p₃ -ᵥ p₂ = r • (p₁ -ᵥ p₂)
⊢ p₃ -ᵥ p₁ = (-r + 1) • (p₂ -ᵥ p₁)

Tactic:
rw [add_smul, ← neg_vsub_eq_vsub_rev p₁ p₂, smul_neg]

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
p₁ p₂ p₃ : P
hp₁p₂ : p₂ -ᵥ p₁ ≠ 0
r : ℝ
hr : r < 0
hpr : p₃ -ᵥ p₂ = r • (p₁ -ᵥ p₂)
⊢ p₃ -ᵥ p₁ = -(-r • (p₁ -ᵥ p₂)) + 1 • -(p₁ -ᵥ p₂)
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Rotation

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
r₁ r₂ : ℝ
⊢ ⟪r₁ • (o.rotation ↑(π / 2)) x, r₂ • x⟫ = 0

Tactic:
by
  rw [inner_smul_right, inner_smul_rotation_pi_div_two_left, mul_zero]

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

Goal state before:
pp: V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
w x y z : V
h : InnerProductGeometry.angle w x = InnerProductGeometry.angle y z
hs : (o.oangle w x).sign = (o.oangle y z).sign
h0 : (w = 0 ∨ x = 0) ∨ y = 0 ∨ z = 0
hswx : (o.oangle w x).sign = 0
hsyz : (o.oangle y z).sign = 0
hwx : InnerProductGeometry.angle w x = π / 2
hyz : InnerProductGeometry.angle y z = π / 2
hpi : π / 2 ≠ π
h0wx : w = 0 ∨ x = 0
h0' : y = 0 ∨ z = 0 ∨ InnerProductGeometry.angle y z = 0 ∨ InnerProductGeometry.angle y z = π
⊢ y = 0 ∨ z = 0

Tactic:
simpa [hyz, Real.pi_pos.ne.symm, hpi] using h0'

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y : V
h : (-o).oangle y x = ↑(π / 2)
⊢ (-o).oangle y (y + x) = ↑(Real.arctan (‖x‖ / ‖y‖))

Tactic:
exact (-o).oangle_add_right_eq_arctan_of_oangle_eq_pi_div_two h

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Affine

Goal state before:
pp: case refine_1
V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p : P
h : p₁ ≠ p₂
hd : dist p₁ p = dist p₂ p
⊢ ∃ r, r • (o.rotation ↑(π / 2)) (p₂ -ᵥ p₁) +ᵥ midpoint ℝ p₁ p₂ = p

Tactic:
have hi : ⟪p₂ -ᵥ p₁, p -ᵥ midpoint ℝ p₁ p₂⟫ = 0 := by
      rw [@dist_eq_norm_vsub' V, @dist_eq_norm_vsub' V, ←
        mul_self_inj (norm_nonneg _) (norm_nonneg _), ← real_inner_self_eq_norm_mul_norm, ←
        real_inner_self_eq_norm_mul_norm] at hd
      simp_rw [vsub_midpoint, ← vsub_sub_vsub_cancel_left p₂ p₁ p, inner_sub_left, inner_add_right,
        inner_smul_right, hd, real_inner_comm (p -ᵥ p₁)]
      abel
    rw [@Orientation.inner_eq_zero_iff_eq_zero_or_eq_smul_rotation_pi_div_two V _ _ _ o,
      or_iff_right (vsub_ne_zero.2 h.symm)] at hi
    rcases hi with ⟨r, hr⟩
    rw [eq_comm, ← eq_vadd_iff_vsub_eq] at hr
    exact ⟨r, hr.symm⟩

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
⊢ o.oangle (x + r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x) = ↑(Real.arctan r⁻¹)

Tactic:
by_cases hr : r = 0

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : r = 0
⊢ o.oangle (x + r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x) = ↑(Real.arctan r⁻¹)

case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : ¬r = 0
⊢ o.oangle (x + r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x) = ↑(Real.arctan r⁻¹)
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
⊢ o.oangle (r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x - x) = ↑(Real.arctan r⁻¹)

Tactic:
by_cases hr : r = 0

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : r = 0
⊢ o.oangle (r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x - x) = ↑(Real.arctan r⁻¹)

case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : ¬r = 0
⊢ o.oangle (r • (o.rotation ↑(π / 2)) x) (r • (o.rotation ↑(π / 2)) x - x) = ↑(Real.arctan r⁻¹)
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
⊢ o.oangle (x - r • (o.rotation ↑(π / 2)) x) x = ↑(Real.arctan r)

Tactic:
by_cases hr : r = 0

Goal state after:
case pos
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : r = 0
⊢ o.oangle (x - r • (o.rotation ↑(π / 2)) x) x = ↑(Real.arctan r)

case neg
V : Type u_1
inst✝¹ : NormedAddCommGroup V
inst✝ : InnerProductSpace ℝ V
hd2 : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x : V
h : x ≠ 0
r : ℝ
hr : ¬r = 0
⊢ o.oangle (x - r • (o.rotation ↑(π / 2)) x) x = ↑(Real.arctan r)
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

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
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ : P
h : ∠ p₁ p₂ p₃ = π / 2
hp₂ : ¬p₂ = p₃
hp₁ : ¬p₁ = p₃
⊢ ∠ p₂ p₃ p₁ < π / 2

Tactic:
exact angle_lt_pi_div_two_of_angle_eq_pi_div_two h (Ne.symm hp₂)

Goal state after:
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.RightAngle

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ : P
h : ∡ p₁ p₂ p₃ = ↑(π / 2)
⊢ (∡ p₂ p₃ p₁).cos = dist p₃ p₂ / dist p₁ p₃

Tactic:
by
  have hs : (∡ p₂ p₃ p₁).sign = 1 := by rw [oangle_rotate_sign, h, Real.Angle.sign_coe_pi_div_two]
  rw [oangle_eq_angle_of_sign_eq_one hs, Real.Angle.cos_coe,
    cos_angle_of_angle_eq_pi_div_two (angle_eq_pi_div_two_of_oangle_eq_pi_div_two h)]

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

Goal state before:
pp: case inl
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
p p' : P
s₁ s₂ : AffineSubspace ℝ P
inst✝¹ : s₁.direction.HasOrthogonalProjection
inst✝ : s₂.direction.HasOrthogonalProjection
hp'₁ : p' ∈ s₁
hp'₂ : p' ∈ s₂
this✝ : Nonempty ↥s₁
this : Nonempty ↥s₂
h' : p ∈ s₁
⊢ dist p ↑((orthogonalProjection s₁) p) = dist p ↑((orthogonalProjection s₂) p) ↔
    ∠ p p' ↑((orthogonalProjection s₁) p) = ∠ p p' ↑((orthogonalProjection s₂) p)

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
p p' : P
s₁ s₂ : AffineSubspace ℝ P
inst✝¹ : s₁.direction.HasOrthogonalProjection
inst✝ : s₂.direction.HasOrthogonalProjection
hp'₁ : p' ∈ s₁
hp'₂ : p' ∈ s₂
this✝ : Nonempty ↥s₁
this : Nonempty ↥s₂
h' : p ∈ s₂
⊢ dist p ↑((orthogonalProjection s₁) p) = dist p ↑((orthogonalProjection s₂) p) ↔
    ∠ p p' ↑((orthogonalProjection s₁) p) = ∠ p p' ↑((orthogonalProjection s₂) p)

Tactic:
· exact dist_orthogonalProjection_eq_iff_angle_eq_aux₁ hp'₁ hp'₂ h'

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
p p' : P
s₁ s₂ : AffineSubspace ℝ P
inst✝¹ : s₁.direction.HasOrthogonalProjection
inst✝ : s₂.direction.HasOrthogonalProjection
hp'₁ : p' ∈ s₁
hp'₂ : p' ∈ s₂
this✝ : Nonempty ↥s₁
this : Nonempty ↥s₂
h' : p ∈ s₂
⊢ dist p ↑((orthogonalProjection s₁) p) = dist p ↑((orthogonalProjection s₂) p) ↔
    ∠ p p' ↑((orthogonalProjection s₁) p) = ∠ p p' ↑((orthogonalProjection s₂) p)
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Basic

Goal state before:
pp: case pos
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : o.oangle x y = -o.oangle y z
hs' : (o.oangle x y).sign = -(o.oangle y z).sign
⊢ o.oangle x z = 0

Tactic:
← o.oangle_add hx hy hz

Goal state after:
case pos
V : Type u_1
inst✝² : NormedAddCommGroup V
inst✝¹ : InnerProductSpace ℝ V
inst✝ : Fact (finrank ℝ V = 2)
o : Orientation ℝ V (Fin 2)
x y z : V
hx : x ≠ 0
hz : z ≠ 0
hy : ¬y = 0
hr : ¬SameRay ℝ x z
hs : ¬(o.oangle x y).sign = (o.oangle y z).sign
hn : o.oangle x y ≠ o.oangle y z
he : o.oangle x y = -o.oangle y z
hs' : (o.oangle x y).sign = -(o.oangle y z).sign
⊢ o.oangle x y + o.oangle y z = 0
Module: Mathlib.Geometry.Euclidean.Angle.Oriented.Affine

Goal state before:
pp: V : Type u_1
P : Type u_2
inst✝⁴ : NormedAddCommGroup V
inst✝³ : InnerProductSpace ℝ V
inst✝² : MetricSpace P
inst✝¹ : NormedAddTorsor V P
hd2 : Fact (finrank ℝ V = 2)
inst✝ : Oriented ℝ V (Fin 2)
p₁ p₂ p₃ p₄ : P
h₁₂ : p₁ ≠ p₂
ha : ∡ p₁ p₂ p₃ = ∡ p₃ p₂ p₄
hs : line[ℝ, p₁, p₂].SOppSide p₃ p₄
h₃₂ : p₃ ≠ p₂
h₄₂ : p₄ ≠ p₂
⊢ ∡ p₁ p₂ ((AffineEquiv.pointReflection ℝ p₂) p₃) = ∡ ((AffineEquiv.pointReflection ℝ p₂) p₃) p₂ p₄

Tactic:
oangle_pointReflection_left h₃₂ h₄₂,

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)
p₁ p₂ p₃ p₄ : P
h₁₂ : p₁ ≠ p₂
ha : ∡ p₁ p₂ p₃ = ∡ p₃ p₂ p₄
hs : line[ℝ, p₁, p₂].SOppSide p₃ p₄
h₃₂ : p₃ ≠ p₂
h₄₂ : p₄ ≠ p₂
⊢ ∡ p₁ p₂ ((AffineEquiv.pointReflection ℝ p₂) p₃) = ∡ p₃ p₂ p₄ + ↑π
Module: Mathlib.Geometry.Euclidean.Sphere.OrthRadius

Goal state before:
pp: case refine_1
V : Type u_1
P : Type u_2
inst✝³ : NormedAddCommGroup V
inst✝² : InnerProductSpace ℝ V
inst✝¹ : MetricSpace P
inst✝ : NormedAddTorsor V P
s : Sphere P
p q : P
h : s.orthRadius p ≤ s.orthRadius q
h' : (ℝ ∙ (p -ᵥ s.center))ᗮ ≤ (ℝ ∙ (q -ᵥ s.center))ᗮ
r : ℝ
hr : r • (p -ᵥ s.center) = q -ᵥ s.center
hp : r - r * r = 0 ∨ ⟪p -ᵥ s.center, p -ᵥ s.center⟫ = 0
⊢ p = q ∨ q = s.center

Tactic:
rcases hp with hp | hp

Goal state after:
case refine_1.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
s : Sphere P
p q : P
h : s.orthRadius p ≤ s.orthRadius q
h' : (ℝ ∙ (p -ᵥ s.center))ᗮ ≤ (ℝ ∙ (q -ᵥ s.center))ᗮ
r : ℝ
hr : r • (p -ᵥ s.center) = q -ᵥ s.center
hp : r - r * r = 0
⊢ p = q ∨ q = s.center

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 q : P
h : s.orthRadius p ≤ s.orthRadius q
h' : (ℝ ∙ (p -ᵥ s.center))ᗮ ≤ (ℝ ∙ (q -ᵥ s.center))ᗮ
r : ℝ
hr : r • (p -ᵥ s.center) = q -ᵥ s.center
hp : ⟪p -ᵥ s.center, p -ᵥ s.center⟫ = 0
⊢ p = q ∨ q = s.center
Module: Mathlib.Geometry.Euclidean.Sphere.OrthRadius

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
s : Sphere P
p q : P
h : dist q s.center ^ 2 - dist p s.center ^ 2 = dist q p ^ 2
h0 : s.radius < 0
⊢ q ∈ s ↔ 0 ≤ s.radius ∧ dist q s.center ^ 2 - dist p s.center ^ 2 = s.radius ^ 2 - dist p s.center ^ 2

Tactic:
simp only [h0.not_ge, sub_left_inj, false_and, iff_false]
    intro hm
    exact h0.not_ge (radius_nonneg_of_mem hm)

Goal state after: