mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Algebra.Lie.Weights.Killing

Goal state before:
pp: R : Type u_1
K : Type u_2
L : Type u_3
inst✝⁹ : CommRing R
inst✝⁸ : LieRing L
inst✝⁷ : LieAlgebra R L
inst✝⁶ : Field K
inst✝⁵ : LieAlgebra K L
inst✝⁴ : FiniteDimensional K L
H : LieSubalgebra K L
inst✝³ : H.IsCartanSubalgebra
inst✝² : IsKilling K L
inst✝¹ : IsTriangularizable K (↥H) L
inst✝ : CharZero K
α : Weight K (↥H) L
hα : α.IsNonZero
h e f : L
t : IsSl2Triple h e f
ht : e ∈ rootSpace H ⇑α ∧ f ∈ rootSpace H (-⇑α)
⊢ LieSubalgebra K L

Tactic:
exact t.toLieSubalgebra K

Goal state after:
Module: Mathlib.RingTheory.Polynomial.Chebyshev

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
n : ℤ
⊢ S R n ^ 2 + S R (n + 1) ^ 2 - X * S R n * S R (n + 1) = 1

Tactic:
by
  induction n with
  | zero => simp; ring
  | succ n ih =>
    have h₁ := S_add_two R n
    linear_combination (norm := ring_nf) (S R (2 + n) - S R n) * h₁ + ih
  | pred n ih =>
    have h₁ := S_sub_one R (-n)
    linear_combination (norm := ring_nf) (S R (-1 - n) - S R (1 - n)) * h₁ + ih

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.Defs

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : AddCommGroup N
inst✝ : Module R N
P : RootPairing ι R M N
i j k : ι
⊢ (P.toLinearMap (P.root j)) ((P.coreflection i) (P.coroot k)) =
    (P.toLinearMap ((P.reflection i) (P.root j))) (P.coroot k)

Tactic:
simp [coreflection_apply_coroot, reflection_apply_root, mul_comm]

Goal state after:
Module: Mathlib.RingTheory.Polynomial.RationalRoot

Goal state before:
pp: A : Type u_1
K : Type u_2
inst✝⁵ : CommRing A
inst✝⁴ : IsDomain A
inst✝³ : UniqueFactorizationMonoid A
inst✝² : Field K
inst✝¹ : Algebra A K
inst✝ : IsFractionRing A K
p : A[X]
r : K
hr : (aeval r) p = 0
⊢ ↑(den A r) ∣ p.leadingCoeff

Tactic:
suffices (den A r : A) ∣ p.leadingCoeff * num A r ^ p.natDegree by
    refine
      dvd_of_dvd_mul_left_of_no_prime_factors (mem_nonZeroDivisors_iff_ne_zero.mp (den A r).2) ?_
        this
    intro q dvd_den dvd_num_pow hq
    apply hq.not_isUnit
    exact num_den_reduced A r (hq.dvd_of_dvd_pow dvd_num_pow) dvd_den
  rw [← coeff_scaleRoots_natDegree]
  apply dvd_term_of_isRoot_of_dvd_terms _ (num_isRoot_scaleRoots_of_aeval_eq_zero hr)
  intro j hj
  by_cases! h : j < p.natDegree
  · rw [coeff_scaleRoots]
    refine (dvd_mul_of_dvd_right ?_ _).mul_right _
    convert! pow_dvd_pow (den A r : A) (Nat.succ_le_iff.mpr (lt_tsub_iff_left.mpr _))
    · exact (pow_one _).symm
    simpa using h
  rw [← natDegree_scaleRoots p (den A r)] at *
  rw [coeff_eq_zero_of_natDegree_lt (lt_of_le_of_ne h hj.symm),
    zero_mul]
  exact dvd_zero _

Goal state after:
Module: Mathlib.RingTheory.Valuation.ValuationRing

Goal state before:
pp: case mk.mk.mk.inl
A : Type u
inst✝⁵ : CommRing A
K : Type v
inst✝⁴ : Field K
inst✝³ : Algebra A K
inst✝² : IsDomain A
inst✝¹ : ValuationRing A
inst✝ : IsFractionRing A K
a✝ : ValueGroup A K
a : K
ha : ¬Quot.mk (⇑(MulAction.orbitRel Aˣ K)) a ≤ 0
b✝ : ValueGroup A K
b : K
c✝ : ValueGroup A K
d : A
⊢ Quot.mk (⇑(MulAction.orbitRel Aˣ K)) ((algebraMap A K) d * b) ≤ Quot.mk (⇑(MulAction.orbitRel Aˣ K)) b

Tactic:
exact ⟨d, by simp [Algebra.smul_def]⟩

Goal state after:
Module: Mathlib.RingTheory.AdicCompletion.Basic

Goal state before:
pp: R : Type u_1
S : Type u_2
T : Type u_3
inst✝⁴ : CommRing R
I : Ideal R
M : Type u_4
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_5
inst✝¹ : AddCommGroup N
inst✝ : Module R N
f : (n : ℕ) → M →ₗ[R] N ⧸ I ^ n • ⊤
h : ∀ {m n : ℕ} (hle : m ≤ n), transitionMap I N hle ∘ₗ f n = f m
x y : M
⊢ ⟨fun n ↦ (f n) (x + y), ⋯⟩ = ⟨fun n ↦ (f n) x, ⋯⟩ + ⟨fun n ↦ (f n) y, ⋯⟩

Tactic:
simp only [map_add]
    rfl

Goal state after:
Module: Mathlib.RingTheory.Valuation.ValuationRing

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝² : Mul R
inst✝¹ : PreValuationRing R
inst✝ : Mul S
f : R →ₙ* S
hf : Function.Surjective ⇑f
a b : S
⊢ ∃ c, a * c = b ∨ b * c = a

Tactic:
obtain ⟨⟨a, rfl⟩, ⟨b, rfl⟩⟩ := hf a, hf b

Goal state after:
R : Type u_1
S : Type u_2
inst✝² : Mul R
inst✝¹ : PreValuationRing R
inst✝ : Mul S
f : R →ₙ* S
hf : Function.Surjective ⇑f
a b : R
⊢ ∃ c, f a * c = f b ∨ f b * c = f a
Module: Mathlib.RingTheory.AdicCompletion.Basic

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
I : Ideal R
M : Type u_4
inst✝¹ : AddCommGroup M
inst✝ : Module R M
h : IsPrecomplete I M
u : AdicCompletion I M
x : ℕ → M
hx : ∀ (n : ℕ), Submodule.Quotient.mk (x n) = ↑u n
m✝ n✝ : ℕ
hmn : m✝ ≤ n✝
⊢ Submodule.Quotient.mk (x m✝) = Submodule.Quotient.mk (x n✝)

Tactic:
hx,

Goal state after:
R : Type u_1
inst✝² : CommRing R
I : Ideal R
M : Type u_4
inst✝¹ : AddCommGroup M
inst✝ : Module R M
h : IsPrecomplete I M
u : AdicCompletion I M
x : ℕ → M
hx : ∀ (n : ℕ), Submodule.Quotient.mk (x n) = ↑u n
m✝ n✝ : ℕ
hmn : m✝ ≤ n✝
⊢ ↑u m✝ = Submodule.Quotient.mk (x n✝)
Module: Mathlib.RingTheory.Jacobson.Ring

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
h : ∀ (P : Ideal R), P.IsPrime → P.jacobson = P
I : Ideal R
hI : I.IsRadical
x : R
hx : x ∈ I.jacobson
P : Ideal R
hP : P ∈ {J | I ≤ J ∧ J.IsPrime}
⊢ x ∈ P

Tactic:
rw [Set.mem_ofPred_eq] at hP

Goal state after:
R : Type u_1
inst✝ : CommRing R
h : ∀ (P : Ideal R), P.IsPrime → P.jacobson = P
I : Ideal R
hI : I.IsRadical
x : R
hx : x ∈ I.jacobson
P : Ideal R
hP : I ≤ P ∧ P.IsPrime
⊢ x ∈ P
Module: Mathlib.RingTheory.DiscreteValuationRing.Basic

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsDiscreteValuationRing R
p q : R
hp : Irreducible p
hq : Irreducible q
u v : Rˣ
m n : ℕ
h : ↑u * p ^ m = ↑v * q ^ n
key : Associated (Multiset.replicate m p).prod (Multiset.replicate n q).prod
⊢ m = n

Tactic:
have := by
    refine Multiset.card_eq_card_of_rel (UniqueFactorizationMonoid.factors_unique ?_ ?_ key)
    all_goals
      intro x hx
      obtain rfl := Multiset.eq_of_mem_replicate hx
      assumption

Goal state after:
R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsDiscreteValuationRing R
p q : R
hp : Irreducible p
hq : Irreducible q
u v : Rˣ
m n : ℕ
h : ↑u * p ^ m = ↑v * q ^ n
key : Associated (Multiset.replicate m p).prod (Multiset.replicate n q).prod
this : (Multiset.replicate m p).card = (Multiset.replicate n q).card
⊢ m = n
Module: Mathlib.RingTheory.Valuation.Basic

Goal state before:
pp: case neg
K : Type u_1
inst✝¹ : DivisionRing K
Γ₀ : Type u_4
inst✝ : LinearOrderedCommGroupWithZero Γ₀
v : Valuation K Γ₀
x : K
h : ¬x = 0
⊢ v x ≤ 1 ∨ v x⁻¹ ≤ 1

Tactic:
simp only [← one_le_val_iff v h, le_total]

Goal state after:
Module: Mathlib.RingTheory.DiscreteValuationRing.TFAE

Goal state before:
pp: case cons.inl
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
inst✝¹ : IsLocalRing R
inst✝ : IsDomain R
I : Ideal R
hI : I ≠ ⊥
h : ¬IsField R
x : R
hx : maximalIdeal R = Ideal.span {x}
hI' : ¬I = ⊤
H : ∀ (r : R), ¬IsUnit r ↔ x ∣ r
this✝ : x ≠ 0
hx' : Irreducible x
fa : R
fh : ∅ ≠ ∅ → (∀ b ∈ ∅, Associated x b) → ∃ n, Associated (x ^ n) ∅.prod
hf₂ : fa ::ₘ ∅ ≠ ∅
this : ∀ b ∈ fa ::ₘ ∅, Associated x b
⊢ ∃ n, Associated (x ^ n) (fa ::ₘ ∅).prod

pp: case cons.inr
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
inst✝¹ : IsLocalRing R
inst✝ : IsDomain R
I : Ideal R
hI : I ≠ ⊥
h : ¬IsField R
x : R
hx : maximalIdeal R = Ideal.span {x}
hI' : ¬I = ⊤
H : ∀ (r : R), ¬IsUnit r ↔ x ∣ r
this✝ : x ≠ 0
hx' : Irreducible x
fa : R
fs : Multiset R
fh : fs ≠ ∅ → (∀ b ∈ fs, Associated x b) → ∃ n, Associated (x ^ n) fs.prod
hf₂ : fa ::ₘ fs ≠ ∅
this : ∀ b ∈ fa ::ₘ fs, Associated x b
hf' : fs ≠ ∅
⊢ ∃ n, Associated (x ^ n) (fa ::ₘ fs).prod

Tactic:
· use 1
      rw [pow_one, Multiset.prod_cons, Multiset.empty_eq_zero, Multiset.prod_zero, mul_one]
      exact this _ (Multiset.mem_cons_self _ _)

Goal state after:
case cons.inr
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
inst✝¹ : IsLocalRing R
inst✝ : IsDomain R
I : Ideal R
hI : I ≠ ⊥
h : ¬IsField R
x : R
hx : maximalIdeal R = Ideal.span {x}
hI' : ¬I = ⊤
H : ∀ (r : R), ¬IsUnit r ↔ x ∣ r
this✝ : x ≠ 0
hx' : Irreducible x
fa : R
fs : Multiset R
fh : fs ≠ ∅ → (∀ b ∈ fs, Associated x b) → ∃ n, Associated (x ^ n) fs.prod
hf₂ : fa ::ₘ fs ≠ ∅
this : ∀ b ∈ fa ::ₘ fs, Associated x b
hf' : fs ≠ ∅
⊢ ∃ n, Associated (x ^ n) (fa ::ₘ fs).prod
Module: Mathlib.RingTheory.DiscreteValuationRing.TFAE

Goal state before:
pp: case a
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
inst✝¹ : IsLocalRing R
inst✝ : IsDomain R
I : Ideal R
hI : I ≠ ⊥
h : ¬IsField R
x : R
hx : maximalIdeal R = Ideal.span {x}
hI' : ¬I = ⊤
H : ∀ (r : R), ¬IsUnit r ↔ x ∣ r
this✝ : x ≠ 0
hx' : Irreducible x
H' : ∀ (r : R), r ≠ 0 → r ∈ nonunits R → ∃ n, Associated (x ^ n) r
this : ∃ n, x ^ n ∈ I
⊢ maximalIdeal R ^ Nat.find this ≤ I

Tactic:
hx,

Goal state after:
case a
R : Type u_1
inst✝³ : CommRing R
inst✝² : IsNoetherianRing R
inst✝¹ : IsLocalRing R
inst✝ : IsDomain R
I : Ideal R
hI : I ≠ ⊥
h : ¬IsField R
x : R
hx : maximalIdeal R = Ideal.span {x}
hI' : ¬I = ⊤
H : ∀ (r : R), ¬IsUnit r ↔ x ∣ r
this✝ : x ≠ 0
hx' : Irreducible x
H' : ∀ (r : R), r ≠ 0 → r ∈ nonunits R → ∃ n, Associated (x ^ n) r
this : ∃ n, x ^ n ∈ I
⊢ Ideal.span {x} ^ Nat.find this ≤ I
Module: Mathlib.RingTheory.DiscreteValuationRing.Basic

Goal state before:
pp: case coe.coe
R : Type u_2
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsDiscreteValuationRing R
x y : R
hx : x ≠ 0
hy : y ≠ 0
vx : ℕ
hvx : (addVal R) x = ↑vx
vy : ℕ
hvy : (addVal R) y = ↑vy
⊢ ↑vx ≤ ↑vy ↔ x ∣ y

Tactic:
rw [← addVal_le_iff_dvd, hvx, hvy]

Goal state after:
case coe.coe
R : Type u_2
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsDiscreteValuationRing R
x y : R
hx : x ≠ 0
hy : y ≠ 0
vx : ℕ
hvx : (addVal R) x = ↑vx
vy : ℕ
hvy : (addVal R) y = ↑vy
⊢ ↑vx ≤ ↑vy ↔ ↑vx ≤ ↑vy
Module: Mathlib.RingTheory.Jacobson.Ring

Goal state before:
pp: case neg
R : Type u_5
inst✝² : CommRing R
inst✝¹ : IsDomain R
hR : IsJacobsonRing R
P : Ideal R[X]
inst✝ : P.IsPrime
hP : ∀ (x : R), C x ∈ P → x = 0
Pb : ¬P = ⊥
P' : Ideal R := comap C P
this : P'.IsPrime
hR' : IsJacobsonRing (R ⧸ P')
p : R[X]
pP : p ∈ P
p0 : map (Ideal.Quotient.mk (comap C P)) p ≠ 0
x : R ⧸ P' := (map (Ideal.Quotient.mk P') p).leadingCoeff
hx : x ≠ 0
⊢ ⊥.jacobson = ⊥

Tactic:
let φ : R ⧸ P' →+* R[X] ⧸ P := Ideal.quotientMap P (C : R →+* R[X]) le_rfl

Goal state after:
case neg
R : Type u_5
inst✝² : CommRing R
inst✝¹ : IsDomain R
hR : IsJacobsonRing R
P : Ideal R[X]
inst✝ : P.IsPrime
hP : ∀ (x : R), C x ∈ P → x = 0
Pb : ¬P = ⊥
P' : Ideal R := comap C P
this : P'.IsPrime
hR' : IsJacobsonRing (R ⧸ P')
p : R[X]
pP : p ∈ P
p0 : map (Ideal.Quotient.mk (comap C P)) p ≠ 0
x : R ⧸ P' := (map (Ideal.Quotient.mk P') p).leadingCoeff
hx : x ≠ 0
φ : R ⧸ P' →+* R[X] ⧸ P := quotientMap P C ⋯
⊢ ⊥.jacobson = ⊥
Module: Mathlib.RingTheory.Jacobson.Ring

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
P : Ideal R[X]
hP : P.IsMaximal
inst✝¹ : IsJacobsonRing R
inst✝ : Nontrivial R
hP' : ∀ (x : R), C x ∈ P → x = 0
P' : Ideal R := comap C P
hP'_prime : P'.IsPrime
m : R[X]
hmem_P : m ∈ P
hm : ⟨m, hmem_P⟩ ≠ 0
hm' : m ≠ 0
φ : R ⧸ P' →+* R[X] ⧸ P := quotientMap P C ⋯
a : R ⧸ P' := (map (Ideal.Quotient.mk P') m).leadingCoeff
M : Submonoid (R ⧸ P') := Submonoid.powers a
hp0' : a = 0
x : R
hx : (Ideal.Quotient.mk (comap C P)) x = 0
⊢ x = 0

Tactic:
by
          rwa [Quotient.eq_zero_iff_mem, (by rwa [eq_bot_iff] : (P.comap C : Ideal R) = ⊥)] at hx

Goal state after:
Module: Mathlib.RingTheory.Jacobson.Ring

Goal state before:
pp: n : ℕ
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsJacobsonRing R
P : Ideal (MvPolynomial (Fin n) R)
hP : P.IsMaximal
⊢ ((Ideal.Quotient.mk P).comp C).IsIntegral

Tactic:
change RingHom.IsIntegral (algebraMap R (MvPolynomial (Fin n) R ⧸ P))

Goal state after:
n : ℕ
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsJacobsonRing R
P : Ideal (MvPolynomial (Fin n) R)
hP : P.IsMaximal
⊢ (algebraMap R (MvPolynomial (Fin n) R ⧸ P)).IsIntegral
Module: Mathlib.Algebra.Ring.SumsOfSquares

Goal state before:
pp: R : Type u_1
inst✝² : Mul R
inst✝¹ : Add R
inst✝ : Zero R
motive : (s : R) → IsSumSq s → Prop
zero : motive 0 ⋯
x s : R
hx : IsSquare x
hs : IsSumSq s
⊢ IsSumSq (x + s)

Tactic:
rcases hx with ⟨_, rfl⟩

Goal state after:
R : Type u_1
inst✝² : Mul R
inst✝¹ : Add R
inst✝ : Zero R
motive : (s : R) → IsSumSq s → Prop
zero : motive 0 ⋯
s : R
hs : IsSumSq s
w✝ : R
⊢ IsSumSq (w✝ * w✝ + s)
Module: Mathlib.RingTheory.Valuation.Basic

Goal state before:
pp: case mp
K : Type u_1
inst✝² : DivisionRing K
Γ₀ : Type u_4
Γ'₀ : Type u_5
inst✝¹ : LinearOrderedCommGroupWithZero Γ₀
inst✝ : LinearOrderedCommGroupWithZero Γ'₀
v : Valuation K Γ₀
v' : Valuation K Γ'₀
⊢ v.IsEquiv v' → ∀ {x : K}, v x < 1 ↔ v' x < 1

pp: case mpr
K : Type u_1
inst✝² : DivisionRing K
Γ₀ : Type u_4
Γ'₀ : Type u_5
inst✝¹ : LinearOrderedCommGroupWithZero Γ₀
inst✝ : LinearOrderedCommGroupWithZero Γ'₀
v : Valuation K Γ₀
v' : Valuation K Γ'₀
⊢ (∀ {x : K}, v x < 1 ↔ v' x < 1) → v.IsEquiv v'

Tactic:
· intro h x
    rw [h.lt_one_iff_lt_one]

Goal state after:
case mpr
K : Type u_1
inst✝² : DivisionRing K
Γ₀ : Type u_4
Γ'₀ : Type u_5
inst✝¹ : LinearOrderedCommGroupWithZero Γ₀
inst✝ : LinearOrderedCommGroupWithZero Γ'₀
v : Valuation K Γ₀
v' : Valuation K Γ'₀
⊢ (∀ {x : K}, v x < 1 ↔ v' x < 1) → v.IsEquiv v'
Module: Mathlib.RingTheory.Valuation.Basic

Goal state before:
pp: K : Type u_1
F : Type u_2
R : Type u_3
inst✝⁴ : DivisionRing K
Γ₀ : Type u_4
Γ'₀ : Type u_5
Γ''₀ : Type u_6
inst✝³ : CommRing R
inst✝² : LinearOrderedCommMonoidWithZero Γ₀
v : Valuation R Γ₀
inst✝¹ : Nontrivial Γ₀
inst✝ : NoZeroDivisors Γ₀
x y : R
hxy : x * y ∈ v.supp
⊢ x ∈ v.supp ∨ y ∈ v.supp

Tactic:
simp only [mem_supp_iff] at hxy ⊢
    rw [v.map_mul x y] at hxy
    exact eq_zero_or_eq_zero_of_mul_eq_zero hxy

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.Reduced

Goal state before:
pp: case refine_1
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁷ : CommRing R
inst✝⁶ : AddCommGroup M
inst✝⁵ : Module R M
inst✝⁴ : AddCommGroup N
inst✝³ : Module R N
P : RootPairing ι R M N
inst✝² : CharZero R
inst✝¹ : IsAddTorsionFree M
inst✝ : P.IsReduced
i j : ι
h : P.root i + P.root j ∈ range ⇑P.root
hij : i = j
⊢ False

pp: case refine_2
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁷ : CommRing R
inst✝⁶ : AddCommGroup M
inst✝⁵ : Module R M
inst✝⁴ : AddCommGroup N
inst✝³ : Module R N
P : RootPairing ι R M N
inst✝² : CharZero R
inst✝¹ : IsAddTorsionFree M
inst✝ : P.IsReduced
i j : ι
h : P.root i + P.root j ∈ range ⇑P.root
hij : P.root i = -P.root j
⊢ 0 ∈ range ⇑P.root

Tactic:
· rw [hij, ← two_smul (R := ℕ)] at h
    exact P.nsmul_notMem_range_root h

Goal state after:
case refine_2
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁷ : CommRing R
inst✝⁶ : AddCommGroup M
inst✝⁵ : Module R M
inst✝⁴ : AddCommGroup N
inst✝³ : Module R N
P : RootPairing ι R M N
inst✝² : CharZero R
inst✝¹ : IsAddTorsionFree M
inst✝ : P.IsReduced
i j : ι
h : P.root i + P.root j ∈ range ⇑P.root
hij : P.root i = -P.root j
⊢ 0 ∈ range ⇑P.root
Module: Mathlib.Algebra.Lie.Weights.RootSystem

Goal state before:
pp: case neg
K : Type u_1
L : Type u_2
inst✝⁷ : Field K
inst✝⁶ : CharZero K
inst✝⁵ : LieRing L
inst✝⁴ : LieAlgebra K L
inst✝³ : IsKilling K L
inst✝² : FiniteDimensional K L
H : LieSubalgebra K L
inst✝¹ : H.IsCartanSubalgebra
inst✝ : IsTriangularizable K (↥H) L
α β : Weight K (↥H) L
hα : α.IsNonZero
x : L
hx : x ∈ rootSpace H ⇑(chainTop (⇑α) β)
hx' : ¬x = 0
e f : L
he : e ∈ rootSpace H ⇑α
hf : f ∈ rootSpace H (-⇑α)
isSl2 : IsSl2Triple (↑(coroot α)) e f
this : isSl2.HasPrimitiveVectorWith x ((chainTop (⇑α) β) (coroot α))
μ : ℕ
hμ : (chainTop (⇑α) β) (coroot α) = ↑μ
⊢ ∃ n, n • x = ⁅coroot α, x⁆

Tactic:
exact ⟨μ, by rw [← Nat.cast_smul_eq_nsmul K, ← hμ, lie_eq_smul_of_mem_rootSpace hx]⟩

Goal state after:
Module: Mathlib.Algebra.Module.Submodule.Union

Goal state before:
pp: ι : Type u_1
K : Type u_2
M : Type u_3
inst✝² : Field K
inst✝¹ : AddCommGroup M
inst✝ : Module K M
p : ι → Submodule K M
h₁ : ∀ (i : ι), p i ≠ ⊤
j : ι
s : Finset ι
hj : j ∉ s
hs : s.Nonempty
h₂ : ↑s.card + 1 < ENat.card K
hj' : ↑(p j) ∪ ⋃ i ∈ s, ↑(p i) = univ
x : M
hx : x ∈ p j
hx₀ : x ≠ 0
y : M
hy : y ∉ p j
hy₀ : y ≠ 0
sxy : Set M := {x_1 | ∃ t, ∃ (_ : t ≠ 0), x + t • y = x_1}
⊢ sxy ∩ ↑(p j) ⊆ ∅

Tactic:
rintro - ⟨⟨t, ht₀, rfl⟩, ht : x + t • y ∈ p j⟩

Goal state after:
ι : Type u_1
K : Type u_2
M : Type u_3
inst✝² : Field K
inst✝¹ : AddCommGroup M
inst✝ : Module K M
p : ι → Submodule K M
h₁ : ∀ (i : ι), p i ≠ ⊤
j : ι
s : Finset ι
hj : j ∉ s
hs : s.Nonempty
h₂ : ↑s.card + 1 < ENat.card K
hj' : ↑(p j) ∪ ⋃ i ∈ s, ↑(p i) = univ
x : M
hx : x ∈ p j
hx₀ : x ≠ 0
y : M
hy : y ∉ p j
hy₀ : y ≠ 0
sxy : Set M := {x_1 | ∃ t, ∃ (_ : t ≠ 0), x + t • y = x_1}
t : K
ht₀ : t ≠ 0
ht : x + t • y ∈ p j
⊢ x + t • y ∈ ∅
Module: Mathlib.Algebra.Module.Submodule.Union

Goal state before:
pp: ι : Type u_1
K : Type u_2
M : Type u_3
inst✝² : Field K
inst✝¹ : AddCommGroup M
inst✝ : Module K M
p : ι → Submodule K M
h₁ : ∀ (i : ι), p i ≠ ⊤
j : ι
s : Finset ι
hj : j ∉ s
hs : s.Nonempty
h₂ : ↑s.card + 1 < ENat.card K
hj' : ↑(p j) ∪ ⋃ i ∈ s, ↑(p i) = univ
x : M
hx : x ∈ p j
hx₀ : x ≠ 0
y : M
hy : y ∉ p j
hy₀ : y ≠ 0
sxy : Set M := {x_1 | ∃ t, ∃ (_ : t ≠ 0), x + t • y = x_1}
hsxy : sxy ⊆ ⋃ i ∈ s, ↑(p i)
f : ↑sxy → ι
hf : ∀ (z : ↑sxy), ↑z ∈ ⋃ (_ : f z ∈ s), ↑(p (f z))
hf' : MapsTo f univ ↑s
z₁ z₂ : ↑sxy
hne : z₁ ≠ z₂
heq : f z₁ = f z₂
⊢ ↑z₁ ∈ p (f z₁)

Tactic:
by specialize hf z₁; simp_all

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.Reduced

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁹ : CommRing R
inst✝⁸ : AddCommGroup M
inst✝⁷ : Module R M
inst✝⁶ : AddCommGroup N
inst✝⁵ : Module R N
P : RootPairing ι R M N
i j : ι
inst✝⁴ : Finite ι
inst✝³ : CharZero R
inst✝² : IsDomain R
inst✝¹ : IsTorsionFree R M
inst✝ : IsTorsionFree R N
h2 : IsSMulRegular R 2
⊢ P.pairing i j = -1 ∧ P.pairing j i = -4 ↔ P.root j = -2 • P.root i

Tactic:
by
  simpa [neg_smul, ← neg_eq_iff_eq_neg] using P.pairing_one_four_iff' i (P.reflectionPerm j j) h2

Goal state after:
Module: Mathlib.LinearAlgebra.QuadraticForm.Prod

Goal state before:
pp: case left
R : Type u_2
M₁ : Type u_3
M₂ : Type u_4
P : Type u_7
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M₁
inst✝⁴ : AddCommMonoid M₂
inst✝³ : AddCommMonoid P
inst✝² : Module R M₁
inst✝¹ : Module R M₂
inst✝ : Module R P
Q₁ : QuadraticMap R M₁ P
Q₂ : QuadraticMap R M₂ P
h : ∀ (a : M₁) (b : M₂), Q₁ a + Q₂ b = 0 → a = 0 ∧ b = 0
x : M₁
hx : Q₁ x = 0
⊢ Q₁ x + Q₂ 0 = 0

Tactic:
hx,

Goal state after:
case left
R : Type u_2
M₁ : Type u_3
M₂ : Type u_4
P : Type u_7
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M₁
inst✝⁴ : AddCommMonoid M₂
inst✝³ : AddCommMonoid P
inst✝² : Module R M₁
inst✝¹ : Module R M₂
inst✝ : Module R P
Q₁ : QuadraticMap R M₁ P
Q₂ : QuadraticMap R M₂ P
h : ∀ (a : M₁) (b : M₂), Q₁ a + Q₂ b = 0 → a = 0 ∧ b = 0
x : M₁
hx : Q₁ x = 0
⊢ 0 + Q₂ 0 = 0
Module: Mathlib.LinearAlgebra.QuadraticForm.Prod

Goal state before:
pp: case right
R : Type u_2
M₁ : Type u_3
M₂ : Type u_4
P : Type u_7
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M₁
inst✝⁴ : AddCommMonoid M₂
inst✝³ : AddCommMonoid P
inst✝² : Module R M₁
inst✝¹ : Module R M₂
inst✝ : Module R P
Q₁ : QuadraticMap R M₁ P
Q₂ : QuadraticMap R M₂ P
h : ∀ (a : M₁) (b : M₂), Q₁ a + Q₂ b = 0 → a = 0 ∧ b = 0
x : M₂
hx : Q₂ x = 0
⊢ Q₁ 0 + Q₂ x = 0

Tactic:
hx,

Goal state after:
case right
R : Type u_2
M₁ : Type u_3
M₂ : Type u_4
P : Type u_7
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M₁
inst✝⁴ : AddCommMonoid M₂
inst✝³ : AddCommMonoid P
inst✝² : Module R M₁
inst✝¹ : Module R M₂
inst✝ : Module R P
Q₁ : QuadraticMap R M₁ P
Q₂ : QuadraticMap R M₂ P
h : ∀ (a : M₁) (b : M₂), Q₁ a + Q₂ b = 0 → a = 0 ∧ b = 0
x : M₂
hx : Q₂ x = 0
⊢ Q₁ 0 + 0 = 0
Module: Mathlib.LinearAlgebra.QuadraticForm.Dual

Goal state before:
pp: ι : Type u_4
R : Type u_5
M : Type u_6
inst✝⁴ : CommRing R
inst✝³ : LinearOrder R
inst✝² : IsStrictOrderedRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
B : LinearMap.BilinForm R M
hB : (BilinMap.toQuadraticMap B).PosDef
f : Module.Dual R M
v : ι → M
hp : ∀ (i : ι), 0 < f (v i)
hn : Pairwise fun i j ↦ (B (v i)) (v j) ≤ 0
s : Finset ι
c : ι → R
hc : ∑ i ∈ s, c i • v i = 0
x : M := ∑ i ∈ s with 0 < c i, c i • v i
hx : x = ∑ i ∈ s with 0 < c i, c i • v i
y : M := ∑ i ∈ s with 0 < -c i, -c i • v i
hy : y = ∑ i ∈ s with 0 < -c i, -c i • v i
⊢ x = y

Tactic:
hx,

Goal state after:
ι : Type u_4
R : Type u_5
M : Type u_6
inst✝⁴ : CommRing R
inst✝³ : LinearOrder R
inst✝² : IsStrictOrderedRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
B : LinearMap.BilinForm R M
hB : (BilinMap.toQuadraticMap B).PosDef
f : Module.Dual R M
v : ι → M
hp : ∀ (i : ι), 0 < f (v i)
hn : Pairwise fun i j ↦ (B (v i)) (v j) ≤ 0
s : Finset ι
c : ι → R
hc : ∑ i ∈ s, c i • v i = 0
x : M := ∑ i ∈ s with 0 < c i, c i • v i
hx : x = ∑ i ∈ s with 0 < c i, c i • v i
y : M := ∑ i ∈ s with 0 < -c i, -c i • v i
hy : y = ∑ i ∈ s with 0 < -c i, -c i • v i
⊢ ∑ i ∈ s with 0 < c i, c i • v i = y
Module: Mathlib.LinearAlgebra.RootSystem.WeylGroup

Goal state before:
pp: case refine_2
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : AddCommGroup N
inst✝ : Module R N
P : RootPairing ι R M N
w : P.Aut
hw : w ∈ P.weylGroup
⊢ ((Equiv.weightHom P).domRestrict P.weylGroup) ⟨w, hw⟩ ∈ Subgroup.closure (range P.reflection)

Tactic:
induction hw using Subgroup.closure_induction'' with

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.WeylGroup

Goal state before:
pp: case refine_1
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : AddCommGroup N
inst✝ : Module R N
P : RootPairing ι R M N
⊢ range (MulOpposite.op ∘ P.coreflection) ⊆ ↑((Equiv.coweightHom P).domRestrict P.weylGroup).range

Tactic:
rintro - ⟨i, rfl⟩
    simp only [MonoidHom.domRestrict_range, Subgroup.coe_map, mem_image,
      SetLike.mem_coe]
    use Equiv.reflection P i
    refine ⟨reflection_mem_weylGroup P i, by simp⟩

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.WeylGroup

Goal state before:
pp: case refine_2
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : AddCommGroup N
inst✝ : Module R N
P : RootPairing ι R M N
w : P.Aut
hw : w ∈ P.weylGroup
⊢ ((Equiv.coweightHom P).domRestrict P.weylGroup) ⟨w, hw⟩ ∈ Subgroup.closure (range (MulOpposite.op ∘ P.coreflection))

Tactic:
induction hw using Subgroup.closure_induction'' with

Goal state after:
Module: Mathlib.LinearAlgebra.RootSystem.WeylGroup

Goal state before:
pp: case refine_2
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : AddCommGroup N
inst✝ : Module R N
P : RootPairing ι R M N
w : P.Aut
hw : w ∈ P.weylGroup
⊢ P.weylGroupToPerm ⟨w, hw⟩ ∈ Subgroup.closure (range P.reflectionPerm)

Tactic:
induction hw using Subgroup.closure_induction'' with

Goal state after:
Module: Mathlib.RepresentationTheory.Basic

Goal state before:
pp: case smul
k : Type u_1
G : Type u_2
V : Type u_3
inst✝³ : CommSemiring k
inst✝² : Monoid G
inst✝¹ : AddCommMonoid V
inst✝ : Module k V
ρ : Representation k G V
x : k[G]
v : ρ.asModule
s : k
y : k[G]
hy : ∀ (t : k), (t • y) • v = t • y • v
t : k
⊢ (t * s) • y • v = t • (s • y) • v

Tactic:
← smul_eq_mul,

Goal state after:
case smul
k : Type u_1
G : Type u_2
V : Type u_3
inst✝³ : CommSemiring k
inst✝² : Monoid G
inst✝¹ : AddCommMonoid V
inst✝ : Module k V
ρ : Representation k G V
x : k[G]
v : ρ.asModule
s : k
y : k[G]
hy : ∀ (t : k), (t • y) • v = t • y • v
t : k
⊢ (t • s) • y • v = t • (s • y) • v
Module: Mathlib.LinearAlgebra.RootSystem.Irreducible

Goal state before:
pp: ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁵ : CommRing R
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
inst✝² : AddCommGroup N
inst✝¹ : Module R N
P : RootPairing ι R M N
inst✝ : P.IsRootSystem
x : M
⊢ x = 0 ↔ ∀ (i : ι), (P.coroot' i) x = 0

Tactic:
refine ⟨fun h ↦ by simp [h], fun h ↦ ?_⟩

Goal state after:
ι : Type u_1
R : Type u_2
M : Type u_3
N : Type u_4
inst✝⁵ : CommRing R
inst✝⁴ : AddCommGroup M
inst✝³ : Module R M
inst✝² : AddCommGroup N
inst✝¹ : Module R N
P : RootPairing ι R M N
inst✝ : P.IsRootSystem
x : M
h : ∀ (i : ι), (P.coroot' i) x = 0
⊢ x = 0