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

Goal state before:
pp: 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 : FiniteDimensional K L
inst✝² : IsKilling K L
H : LieSubalgebra K L
inst✝¹ : H.IsCartanSubalgebra
inst✝ : IsTriangularizable K (↥H) L
q : Submodule K (Dual K ↥H)
hq : ∀ (i : ↥LieSubalgebra.root), q ∈ End.invtSubmodule ↑((rootSystem H).reflection i)
χ : Weight K (↥H) L
x_χ m_α : L
hx_χ : x_χ ∈ genWeightSpace L ⇑χ
α : Weight K (↥H) L
hαq : Weight.toLinear K (↥H) L α ∈ q
hα₀ : α.IsNonZero
hm_α : m_α ∈ genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α) ⊔ corootSubmodule α
hm_α_original : m_α ∈ sl2SubmoduleOfRoot hα₀
m_αneg : L
hm_αneg : m_αneg ∈ ↑(genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α))
m_h : L
hm_h : m_h ∈ ↑(corootSubmodule α)
hm_eq : m_αneg + m_h = m_α
m_pos : L
hm_pos : m_pos ∈ ↑(genWeightSpace L ⇑α)
m_neg : L
hm_neg : m_neg ∈ ↑(genWeightSpace L (-⇑α))
hm_αneg_eq : m_pos + m_neg = m_αneg
hm_α_decomp : m_α = m_pos + m_neg + m_h
h_bracket_sum : ⁅x_χ, m_α⁆ = ⁅x_χ, m_pos⁆ + ⁅x_χ, m_neg⁆ + ⁅x_χ, m_h⁆
w_plus : ¬Weight.toLinear K (↥H) L χ + Weight.toLinear K (↥H) L α = 0
w_minus : Weight.toLinear K (↥H) L χ - Weight.toLinear K (↥H) L α = 0
h e f : L
ht : IsSl2Triple h e f
he : e ∈ rootSpace H ⇑α
hf : f ∈ rootSpace H (-⇑α)
hx_χ_pos : x_χ ∈ genWeightSpace L ⇑(Weight.toLinear K (↥H) L α)
c : K
hc : c • ⟨e, he⟩ = ⟨x_χ, hx_χ_pos⟩
⊢ x_χ = c • e + 0 • f + 0 • ⁅e, f⁆

Tactic:
simpa using hc.symm

Goal state after:
Module: Mathlib.Algebra.Module.FinitePresentation

Goal state before:
pp: case map_units.right
R : Type u_3
M : Type u_4
N : Type u_5
N'✝ : Type ?u.18
inst✝¹⁴ : CommRing R
inst✝¹³ : AddCommGroup M
inst✝¹² : Module R M
inst✝¹¹ : AddCommGroup N
inst✝¹⁰ : Module R N
inst✝⁹ : AddCommGroup N'✝
inst✝⁸ : Module R N'✝
S : Submonoid R
f✝ : N →ₗ[R] N'✝
inst✝⁷ : IsLocalizedModule S f✝
M' : Type u_1
inst✝⁶ : AddCommGroup M'
inst✝⁵ : Module R M'
f : M →ₗ[R] M'
inst✝⁴ : IsLocalizedModule S f
N' : Type u_2
inst✝³ : AddCommGroup N'
inst✝² : Module R N'
g : N →ₗ[R] N'
inst✝¹ : IsLocalizedModule S g
inst✝ : FinitePresentation R M
s : ↥S
this : Function.Bijective ⇑((algebraMap R (End R N')) ↑s)
⊢ Function.Surjective ⇑((algebraMap R (End R (M' →ₗ[R] N'))) ↑s)

Tactic:
intro h

Goal state after:
case map_units.right
R : Type u_3
M : Type u_4
N : Type u_5
N'✝ : Type ?u.18
inst✝¹⁴ : CommRing R
inst✝¹³ : AddCommGroup M
inst✝¹² : Module R M
inst✝¹¹ : AddCommGroup N
inst✝¹⁰ : Module R N
inst✝⁹ : AddCommGroup N'✝
inst✝⁸ : Module R N'✝
S : Submonoid R
f✝ : N →ₗ[R] N'✝
inst✝⁷ : IsLocalizedModule S f✝
M' : Type u_1
inst✝⁶ : AddCommGroup M'
inst✝⁵ : Module R M'
f : M →ₗ[R] M'
inst✝⁴ : IsLocalizedModule S f
N' : Type u_2
inst✝³ : AddCommGroup N'
inst✝² : Module R N'
g : N →ₗ[R] N'
inst✝¹ : IsLocalizedModule S g
inst✝ : FinitePresentation R M
s : ↥S
this : Function.Bijective ⇑((algebraMap R (End R N')) ↑s)
h : M' →ₗ[R] N'
⊢ ∃ a, ((algebraMap R (End R (M' →ₗ[R] N'))) ↑s) a = h
Module: Mathlib.Algebra.Module.FinitePresentation

Goal state before:
pp: case surj
R : Type u_3
M : Type u_4
N : Type u_5
N'✝ : Type ?u.18
inst✝¹⁴ : CommRing R
inst✝¹³ : AddCommGroup M
inst✝¹² : Module R M
inst✝¹¹ : AddCommGroup N
inst✝¹⁰ : Module R N
inst✝⁹ : AddCommGroup N'✝
inst✝⁸ : Module R N'✝
S : Submonoid R
f✝ : N →ₗ[R] N'✝
inst✝⁷ : IsLocalizedModule S f✝
M' : Type u_1
inst✝⁶ : AddCommGroup M'
inst✝⁵ : Module R M'
f : M →ₗ[R] M'
inst✝⁴ : IsLocalizedModule S f
N' : Type u_2
inst✝³ : AddCommGroup N'
inst✝² : Module R N'
g : N →ₗ[R] N'
inst✝¹ : IsLocalizedModule S g
inst✝ : FinitePresentation R M
⊢ ∀ (y : M' →ₗ[R] N'), ∃ x, x.2 • y = (IsLocalizedModule.map S f g) x.1

Tactic:
intro h

Goal state after:
case surj
R : Type u_3
M : Type u_4
N : Type u_5
N'✝ : Type ?u.18
inst✝¹⁴ : CommRing R
inst✝¹³ : AddCommGroup M
inst✝¹² : Module R M
inst✝¹¹ : AddCommGroup N
inst✝¹⁰ : Module R N
inst✝⁹ : AddCommGroup N'✝
inst✝⁸ : Module R N'✝
S : Submonoid R
f✝ : N →ₗ[R] N'✝
inst✝⁷ : IsLocalizedModule S f✝
M' : Type u_1
inst✝⁶ : AddCommGroup M'
inst✝⁵ : Module R M'
f : M →ₗ[R] M'
inst✝⁴ : IsLocalizedModule S f
N' : Type u_2
inst✝³ : AddCommGroup N'
inst✝² : Module R N'
g : N →ₗ[R] N'
inst✝¹ : IsLocalizedModule S g
inst✝ : FinitePresentation R M
h : M' →ₗ[R] N'
⊢ ∃ x, x.2 • h = (IsLocalizedModule.map S f g) x.1
Module: Mathlib.Algebra.Lie.Weights.IsSimple

Goal state before:
pp: 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 : FiniteDimensional K L
inst✝² : IsKilling K L
H : LieSubalgebra K L
inst✝¹ : H.IsCartanSubalgebra
inst✝ : IsTriangularizable K (↥H) L
q : Submodule K (Dual K ↥H)
hq : ∀ (i : ↥LieSubalgebra.root), q ∈ End.invtSubmodule ↑((rootSystem H).reflection i)
χ : Weight K (↥H) L
x_χ m_α : L
hx_χ : x_χ ∈ genWeightSpace L ⇑χ
α : Weight K (↥H) L
hαq : Weight.toLinear K (↥H) L α ∈ q
hα₀ : α.IsNonZero
hm_α : m_α ∈ genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α) ⊔ corootSubmodule α
hm_α_original : m_α ∈ sl2SubmoduleOfRoot hα₀
m_αneg : L
hm_αneg : m_αneg ∈ ↑(genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α))
m_h : L
hm_h : m_h ∈ ↑(corootSubmodule α)
hm_eq : m_αneg + m_h = m_α
m_pos : L
hm_pos : m_pos ∈ ↑(genWeightSpace L ⇑α)
m_neg : L
hm_neg : m_neg ∈ ↑(genWeightSpace L (-⇑α))
hm_αneg_eq : m_pos + m_neg = m_αneg
hm_α_decomp : m_α = m_pos + m_neg + m_h
h_bracket_sum : ⁅x_χ, m_α⁆ = ⁅x_χ, m_pos⁆ + ⁅x_χ, m_neg⁆ + ⁅x_χ, m_h⁆
w_plus : ¬Weight.toLinear K (↥H) L χ + Weight.toLinear K (↥H) L α = 0
w_minus : ¬Weight.toLinear K (↥H) L χ - Weight.toLinear K (↥H) L α = 0
w_chi : Weight.toLinear K (↥H) L χ = 0
⊢ x_χ ∈ H.toLieSubmodule

Tactic:
rw [← rootSpace_zero_eq K L H]

Goal state after:
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 : FiniteDimensional K L
inst✝² : IsKilling K L
H : LieSubalgebra K L
inst✝¹ : H.IsCartanSubalgebra
inst✝ : IsTriangularizable K (↥H) L
q : Submodule K (Dual K ↥H)
hq : ∀ (i : ↥LieSubalgebra.root), q ∈ End.invtSubmodule ↑((rootSystem H).reflection i)
χ : Weight K (↥H) L
x_χ m_α : L
hx_χ : x_χ ∈ genWeightSpace L ⇑χ
α : Weight K (↥H) L
hαq : Weight.toLinear K (↥H) L α ∈ q
hα₀ : α.IsNonZero
hm_α : m_α ∈ genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α) ⊔ corootSubmodule α
hm_α_original : m_α ∈ sl2SubmoduleOfRoot hα₀
m_αneg : L
hm_αneg : m_αneg ∈ ↑(genWeightSpace L ⇑α ⊔ genWeightSpace L (-⇑α))
m_h : L
hm_h : m_h ∈ ↑(corootSubmodule α)
hm_eq : m_αneg + m_h = m_α
m_pos : L
hm_pos : m_pos ∈ ↑(genWeightSpace L ⇑α)
m_neg : L
hm_neg : m_neg ∈ ↑(genWeightSpace L (-⇑α))
hm_αneg_eq : m_pos + m_neg = m_αneg
hm_α_decomp : m_α = m_pos + m_neg + m_h
h_bracket_sum : ⁅x_χ, m_α⁆ = ⁅x_χ, m_pos⁆ + ⁅x_χ, m_neg⁆ + ⁅x_χ, m_h⁆
w_plus : ¬Weight.toLinear K (↥H) L χ + Weight.toLinear K (↥H) L α = 0
w_minus : ¬Weight.toLinear K (↥H) L χ - Weight.toLinear K (↥H) L α = 0
w_chi : Weight.toLinear K (↥H) L χ = 0
⊢ x_χ ∈ rootSpace H 0
Module: Mathlib.RingTheory.MvPolynomial.Localization

Goal state before:
pp: R : Type u_2
inst✝³ : CommRing R
S : Type u_3
inst✝² : CommRing S
inst✝¹ : Algebra R S
r : R
inst✝ : Away r S
x : R
⊢ (((auxHom S r).comp (auxInv S r)).comp (algebraMap R S)) x = ((RingHom.id S).comp (algebraMap R S)) x

Tactic:
simp [auxInv]

Goal state after:
Module: Mathlib.RingTheory.MvPolynomial.Localization

Goal state before:
pp: case hC
R : Type u_2
inst✝³ : CommRing R
S : Type u_3
inst✝² : CommRing S
inst✝¹ : Algebra R S
r : R
inst✝ : Away r S
x : R
⊢ ((((auxInv S r).comp (auxHom S r).toRingHom).comp (Ideal.Quotient.mk (Ideal.span {C r * X () - 1}))).comp C) x =
    (((RingHom.id (MvPolynomial Unit R ⧸ Ideal.span {C r * X () - 1})).comp
            (Ideal.Quotient.mk (Ideal.span {C r * X () - 1}))).comp
        C)
      x

Tactic:
simp [auxInv]

Goal state after:
Module: Mathlib.Algebra.Module.Presentation.Free

Goal state before:
pp: A : Type u
inst✝⁵ : Ring A
relations : Relations A
M : Type v
inst✝⁴ : AddCommGroup M
inst✝³ : Module A M
inst✝² : IsEmpty relations.R
N✝ : Type w
inst✝¹ : AddCommGroup N✝
inst✝ : Module A N✝
f✝ f'✝ : (relations.G →₀ A) →ₗ[A] N✝
h : relations.solutionFinsupp.postcomp f✝ = relations.solutionFinsupp.postcomp f'✝
⊢ f✝ = f'✝

Tactic:
ext; apply Solution.congr_var h

Goal state after:
Module: Mathlib.RingTheory.Extension.Generators

Goal state before:
pp: R : Type u
ι : Type w
inst✝ : CommRing R
⊢ (mvPolynomial R ι).ker = ⊥

Tactic:
simp [ker_eq_ker_aeval_val, SetLike.ext_iff, aeval_X_left]

Goal state after:
Module: Mathlib.RingTheory.Extension.Generators

Goal state before:
pp: case a.convert_4.monomial
R : Type u
S : Type v
ι : Type w
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
ι' : Type u_3
T : Type u_7
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
Q : Generators S T ι'
P : Generators R S ι
this✝ : DecidableEq (ι' →₀ ℕ) := Classical.decEq (ι' →₀ ℕ)
e : (ι' ⊕ ι →₀ ℕ) ≃+ (ι' →₀ ℕ) × (ι →₀ ℕ) := Finsupp.sumFinsuppAddEquivProdFinsupp
i : ι' →₀ ℕ
this :
  ∀ (x : (Q.comp P).Ring),
    (Function.support fun a ↦ if a.1 = i then (aeval P.val) ((monomial a.2) (coeff (e.symm a) x)) else 0) ⊆
      ↑(Finset.map (↑e).toEmbedding (support x))
v : ι' ⊕ ι →₀ ℕ
a : R
⊢ (∑ᶠ (i_1 : (ι' →₀ ℕ) × (ι →₀ ℕ)),
      if i_1.1 = i then (aeval P.val) ((monomial i_1.2) (coeff (e.symm i_1) ((monomial v) a))) else 0) =
    coeff i ((Q.ofComp P).toAlgHom ((monomial v) a))

Tactic:
| monomial v a =>

Goal state after:
Module: Mathlib.RingTheory.Extension.Cotangent.Basic

Goal state before:
pp: R : Type u
S : Type v
inst✝²² : CommRing R
inst✝²¹ : CommRing S
inst✝²⁰ : Algebra R S
P : Extension R S
R' : Type u'
S' : Type v'
inst✝¹⁹ : CommRing R'
inst✝¹⁸ : CommRing S'
inst✝¹⁷ : Algebra R' S'
P' : Extension R' S'
inst✝¹⁶ : Algebra R R'
inst✝¹⁵ : Algebra S S'
inst✝¹⁴ : Algebra R S'
inst✝¹³ : IsScalarTower R R' S'
R'' : Type u''
S'' : Type v''
inst✝¹² : CommRing R''
inst✝¹¹ : CommRing S''
inst✝¹⁰ : Algebra R'' S''
P'' : Extension R'' S''
inst✝⁹ : Algebra R R''
inst✝⁸ : Algebra S S''
inst✝⁷ : Algebra R S''
inst✝⁶ : IsScalarTower R R'' S''
inst✝⁵ : Algebra R' R''
inst✝⁴ : Algebra S' S''
inst✝³ : Algebra R' S''
inst✝² : IsScalarTower R' R'' S''
inst✝¹ : IsScalarTower R R' R''
inst✝ : IsScalarTower S S' S''
f : P.Hom P'
⊢ P.CotangentSpace →ₗ[S] P'.CotangentSpace

Tactic:
letI := ((algebraMap S S').comp (algebraMap P.Ring S)).toAlgebra
  haveI : IsScalarTower P.Ring S S' := IsScalarTower.of_algebraMap_eq' rfl
  letI := f.toAlgHom.toAlgebra
  haveI : IsScalarTower P.Ring P'.Ring S' :=
    IsScalarTower.of_algebraMap_eq (fun x ↦ (f.algebraMap_toRingHom x).symm)
  apply LinearMap.liftBaseChange
  refine (TensorProduct.mk _ _ _ 1).restrictScalars _ ∘ₗ KaehlerDifferential.map R R' P.Ring P'.Ring

Goal state after:
Module: Mathlib.LinearAlgebra.TensorProduct.Vanishing

Goal state before:
pp: R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
hMN : ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n
M' : Submodule R M
⊢ Injective ⇑(rTensor N M'.subtype)

Tactic:
by
  apply (injective_iff_map_eq_zero _).mpr
  rintro x hx
  obtain ⟨s, rfl⟩ := exists_finset x
  rw [← Finset.sum_attach]
  apply sum_tmul_eq_zero_of_vanishesTrivially
  simp only [map_sum, rTensor_tmul, coe_subtype] at hx
  have e := (Fintype.equivFin s).symm
  rw [← Finset.sum_coe_sort, ← e.sum_comp] at hx
  have := hMN hx
  rw [← e.vanishesTrivially_comp]
  unfold VanishesTrivially at this ⊢
  convert! this
  symm
  convert! (injective_iff_map_eq_zero' _).mp (injective_subtype M') _
  simp

Goal state after:
Module: Mathlib.LinearAlgebra.TensorProduct.Vanishing

Goal state before:
pp: case mp
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
⊢ (∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n) →
    ∀ (M' : Submodule R M), Injective ⇑(rTensor N M'.subtype)

Tactic:
intro h

Goal state after:
case mp
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
h : ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n
⊢ ∀ (M' : Submodule R M), Injective ⇑(rTensor N M'.subtype)
Module: Mathlib.LinearAlgebra.TensorProduct.Vanishing

Goal state before:
pp: case mpr
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
⊢ (∀ (M' : Submodule R M), Injective ⇑(rTensor N M'.subtype)) →
    ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n

Tactic:
intro h

Goal state after:
case mpr
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
h : ∀ (M' : Submodule R M), Injective ⇑(rTensor N M'.subtype)
⊢ ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n
Module: Mathlib.LinearAlgebra.TensorProduct.Vanishing

Goal state before:
pp: case mp
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
⊢ (∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n) →
    ∀ (M' : Submodule R M), M'.FG → Injective ⇑(rTensor N M'.subtype)

Tactic:
intro h

Goal state after:
case mp
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
h : ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n
⊢ ∀ (M' : Submodule R M), M'.FG → Injective ⇑(rTensor N M'.subtype)
Module: Mathlib.LinearAlgebra.TensorProduct.Vanishing

Goal state before:
pp: case mpr
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
⊢ (∀ (M' : Submodule R M), M'.FG → Injective ⇑(rTensor N M'.subtype)) →
    ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n

Tactic:
intro h

Goal state after:
case mpr
R : Type u_1
inst✝⁴ : CommRing R
M : Type u_2
inst✝³ : AddCommGroup M
inst✝² : Module R M
N : Type u_3
inst✝¹ : AddCommGroup N
inst✝ : Module R N
h : ∀ (M' : Submodule R M), M'.FG → Injective ⇑(rTensor N M'.subtype)
⊢ ∀ {l : ℕ} {m : Fin l → M} {n : Fin l → N}, ∑ i, m i ⊗ₜ[R] n i = 0 → VanishesTrivially R m n
Module: Mathlib.RingTheory.Flat.EquationalCriterion

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : AddCommGroup M
inst✝⁴ : Module R M
inst✝³ : Flat R M
P : Type u_3
inst✝² : AddCommGroup P
inst✝¹ : Module R P
inst✝ : FinitePresentation R P
h₁ : P →ₗ[R] M
w✝ : ℕ
K : Submodule R (Fin w✝ → R)
ϕ : P ≃ₗ[R] (Fin w✝ → R) ⧸ K
hK : K.FG
this✝ : Module.Finite R ↥K
this : (h₁ ∘ₗ ↑ϕ.symm ∘ₗ K.mkQ) ∘ₗ K.subtype = 0
k : ℕ
a : (Fin w✝ → R) →ₗ[R] Fin k →₀ R
y : (Fin k →₀ R) →ₗ[R] M
hay : h₁ ∘ₗ ↑ϕ.symm ∘ₗ K.mkQ = y ∘ₗ a
ha : a ∘ₗ K.subtype = 0
⊢ K ≤ a.ker

Tactic:
by rwa [← range_le_ker_iff, Submodule.range_subtype] at ha

Goal state after:
Module: Mathlib.RingTheory.Localization.Finiteness

Goal state before:
pp: R : Type u
inst✝¹⁰ : CommSemiring R
M : Type v
inst✝⁹ : AddCommMonoid M
inst✝⁸ : Module R M
N : Submodule R M
s : Set R
hs : Ideal.span s = ⊤
Mₚ : ↑s → Type u_1
inst✝⁷ : (g : ↑s) → AddCommMonoid (Mₚ g)
inst✝⁶ : (g : ↑s) → Module R (Mₚ g)
Rₚ : ↑s → Type u_2
inst✝⁵ : (g : ↑s) → CommSemiring (Rₚ g)
inst✝⁴ : (g : ↑s) → Algebra R (Rₚ g)
inst✝³ : ∀ (g : ↑s), IsLocalization.Away (↑g) (Rₚ g)
inst✝² : (g : ↑s) → Module (Rₚ g) (Mₚ g)
inst✝¹ : ∀ (g : ↑s), IsScalarTower R (Rₚ g) (Mₚ g)
ϕ : (g : ↑s) → M →ₗ[R] Mₚ g
inst✝ : ∀ (g : ↑s), IsLocalizedModule (Submonoid.powers ↑g) (ϕ g)
H : ∀ (g : ↑s), (localized' (Rₚ g) (Submonoid.powers ↑g) (ϕ g) N).FG
⊢ N.FG

Tactic:
simp [← Module.Finite.iff_fg, Module.Finite.of_localizationSpan' s hs
    (fun g ↦ N.toLocalized' (Rₚ g) (Submonoid.powers g.1) (ϕ g))
    (fun g ↦ Module.Finite.iff_fg.mpr (H g))]

Goal state after:
Module: Mathlib.LinearAlgebra.Alternating.Uncurry.Fin

Goal state before:
pp: R : Type u_1
M : Type u_2
N : Type u_4
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : AddCommGroup N
inst✝¹ : Module R M
inst✝ : Module R N
n : ℕ
f : M [⋀^Fin (n + 1)]→ₗ[R] N
⊢ alternatizeUncurryFin f.curryLeft = (n + 1) • f

Tactic:
by
  ext v
  simp [alternatizeUncurryFin_apply, ← map_insertNth]

Goal state after:
Module: Mathlib.RingTheory.LocalRing.Module

Goal state before:
pp: R : Type u_1
M : Type u_2
inst✝⁴ : CommRing R
inst✝³ : AddCommGroup M
inst✝² : Module R M
inst✝¹ : IsLocalRing R
inst✝ : FinitePresentation R M
ι : Type u_5
v : ι → M
hli : LinearIndependent k (⇑((TensorProduct.mk R k M) 1) ∘ v)
hsp : Submodule.span k (Set.range (⇑((TensorProduct.mk R k M) 1) ∘ v)) = ⊤
H : Function.Injective ⇑(LinearMap.rTensor M (Submodule.subtype 𝔪))
bk : Basis ι k (k ⊗[R] M) := Basis.mk hli ⋯
this✝¹ : Finite ι
this✝ : Fintype ι := Fintype.ofFinite ι
i : (ι →₀ R) →ₗ[R] M := Finsupp.linearCombination R v
hi : Surjective ⇑i
this : Module.Finite R ↥i.ker
⊢ (ι →₀ R) ≃ₗ[R] M

Tactic:
by
    refine LinearEquiv.ofBijective i ⟨?_, hi⟩
    -- By Nakayama's lemma, it suffices to show that `k ⊗ ker(i) = 0`.
    rw [← LinearMap.ker_eq_bot, ← Submodule.subsingleton_iff_eq_bot,
      ← IsLocalRing.subsingleton_tensorProduct (R := R), subsingleton_iff_forall_eq 0]
    have : Function.Surjective (i.baseChange k) := i.lTensor_surjective _ hi
    -- By construction, `k ⊗ i : kᴵ → k ⊗ M` is bijective.
    have hi' : Function.Bijective (i.baseChange k) := by
      refine ⟨?_, this⟩
      rw [← LinearMap.ker_eq_bot (M := k ⊗[R] (ι →₀ R)) (f := i.baseChange k),
        ← Submodule.finrank_eq_zero (R := k) (M := k ⊗[R] (ι →₀ R)),
        ← Nat.add_right_inj (n := Module.finrank k (LinearMap.range <| i.baseChange k)),
        LinearMap.finrank_range_add_finrank_ker (V := k ⊗[R] (ι →₀ R)),
        LinearMap.range_eq_top.mpr this, finrank_top]
      simp only [Module.finrank_tensorProduct, Module.finrank_self,
        Module.finrank_finsupp_self, one_mul, add_zero]
      rw [Module.finrank_eq_card_basis bk]
    -- On the other hand, `m ⊗ M → M` injective => `Tor₁(k, M) = 0` => `k ⊗ ker(i) → kᴵ` injective.
    intro x
    refine lTensor_injective_of_exact_of_exact_of_rTensor_injective
      (N₁ := LinearMap.ker i) (N₂ := ι →₀ R) (N₃ := M)
      (f₁ := (𝔪).subtype) (f₂ := Submodule.mkQ 𝔪)
      (g₁ := (LinearMap.ker i).subtype) (g₂ := i) (LinearMap.exact_subtype_mkQ 𝔪)
      (Submodule.mkQ_surjective _) (LinearMap.exact_subtype_ker_map i) hi H ?_ ?_
    · apply Module.Flat.lTensor_preserves_injective_linearMap
      exact Subtype.val_injective
    · apply hi'.injective
      rw [LinearMap.baseChange_eq_ltensor]
      erw [← LinearMap.comp_apply (i.lTensor k), ← LinearMap.lTensor_comp]
      rw [(LinearMap.exact_subtype_ker_map i).linearMap_comp_eq_zero]
      simp only [LinearMap.lTensor_zero, LinearMap.zero_apply, map_zero]

Goal state after:
Module: Mathlib.LinearAlgebra.PiTensorProduct.Basic

Goal state before:
pp: ι : Type u_1
R : Type u_4
inst✝² : CommSemiring R
s : ι → Type u_7
inst✝¹ : (i : ι) → AddCommMonoid (s i)
inst✝ : (i : ι) → Module R (s i)
x y : ⨂[R] (i : ι), s i
p q : FreeAddMonoid (R × ((i : ι) → s i))
hp : p ∈ x.lifts
hq : q ∈ y.lifts
⊢ p + q ∈ (x + y).lifts

Tactic:
simp only [lifts, Set.mem_ofPred_eq, AddCon.coe_add]

Goal state after:
ι : Type u_1
R : Type u_4
inst✝² : CommSemiring R
s : ι → Type u_7
inst✝¹ : (i : ι) → AddCommMonoid (s i)
inst✝ : (i : ι) → Module R (s i)
x y : ⨂[R] (i : ι), s i
p q : FreeAddMonoid (R × ((i : ι) → s i))
hp : p ∈ x.lifts
hq : q ∈ y.lifts
⊢ ↑p + ↑q = x + y
Module: Mathlib.LinearAlgebra.PiTensorProduct.Basic

Goal state before:
pp: ι : Type u_1
R : Type u_4
inst✝⁶ : CommSemiring R
s : ι → Type u_7
inst✝⁵ : (i : ι) → AddCommMonoid (s i)
inst✝⁴ : (i : ι) → Module R (s i)
t : ι → Type u_11
t' : ι → Type u_12
inst✝³ : (i : ι) → AddCommMonoid (t i)
inst✝² : (i : ι) → Module R (t i)
inst✝¹ : (i : ι) → AddCommMonoid (t' i)
inst✝ : (i : ι) → Module R (t' i)
g : (i : ι) → t i →ₗ[R] t' i
f : (i : ι) → s i →ₗ[R] t i
x✝ : (i : ι) → s i
⊢ ((map fun i ↦ g i ∘ₗ f i).compMultilinearMap (tprod R)) x✝ = ((map g ∘ₗ map f).compMultilinearMap (tprod R)) x✝

Tactic:
simp only [LinearMap.compMultilinearMap_apply, map_tprod, LinearMap.coe_comp, Function.comp_apply]

Goal state after:
Module: Mathlib.RingTheory.LocalRing.Module

Goal state before:
pp: case mpr
R : Type u_1
M : Type u_2
N : Type u_3
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : AddCommGroup N
inst✝⁵ : Module R M
inst✝⁴ : Module R N
inst✝³ : IsLocalRing R
inst✝² : Module.Finite R M
inst✝¹ : Module.Finite R N
inst✝ : Free R N
l : M →ₗ[R] N
⊢ Function.Injective ⇑(LinearMap.lTensor k l) → ∃ l', l' ∘ₗ l = LinearMap.id

Tactic:
intro h

Goal state after:
case mpr
R : Type u_1
M : Type u_2
N : Type u_3
inst✝⁸ : CommRing R
inst✝⁷ : AddCommGroup M
inst✝⁶ : AddCommGroup N
inst✝⁵ : Module R M
inst✝⁴ : Module R N
inst✝³ : IsLocalRing R
inst✝² : Module.Finite R M
inst✝¹ : Module.Finite R N
inst✝ : Free R N
l : M →ₗ[R] N
h : Function.Injective ⇑(LinearMap.lTensor k l)
⊢ ∃ l', l' ∘ₗ l = LinearMap.id
Module: Mathlib.RingTheory.UniqueFactorizationDomain.ClassGroup

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsGCDMonoid R
I : Ideal R
hI : IsUnit ↑I
a : R
K : Ideal R
ha0 : a ≠ 0
h : (↑I)⁻¹ = spanSingleton R⁰ ((algebraMap R (FractionRing R)) a)⁻¹ * ↑K
⊢ ↑I * ↑K = spanSingleton R⁰ ((algebraMap R (FractionRing R)) a)

Tactic:
rw [← mul_inv_cancel_iff_isUnit] at hI

Goal state after:
R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsGCDMonoid R
I : Ideal R
hI : ↑I * (↑I)⁻¹ = 1
a : R
K : Ideal R
ha0 : a ≠ 0
h : (↑I)⁻¹ = spanSingleton R⁰ ((algebraMap R (FractionRing R)) a)⁻¹ * ↑K
⊢ ↑I * ↑K = spanSingleton R⁰ ((algebraMap R (FractionRing R)) a)
Module: Mathlib.RingTheory.ClassGroup.Basic

Goal state before:
pp: case mp
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsDomain R
I : (FractionalIdeal R⁰ (FractionRing R))ˣ
I' : Ideal R
hI : ↑I = ↑I'
x : R
hx : x ≠ 0
i : R
_hi : i ∈ I'
hy : x * i ≠ 0
h : Ideal.span {x} * I' = Ideal.span {x * i}
⊢ ∃ x, x ≠ 0 ∧ I' = Ideal.span {x}

Tactic:
← Ideal.span_singleton_mul_span_singleton,

Goal state after:
case mp
R : Type u_1
inst✝¹ : CommRing R
inst✝ : IsDomain R
I : (FractionalIdeal R⁰ (FractionRing R))ˣ
I' : Ideal R
hI : ↑I = ↑I'
x : R
hx : x ≠ 0
i : R
_hi : i ∈ I'
hy : x * i ≠ 0
h : Ideal.span {x} * I' = Ideal.span {x} * Ideal.span {i}
⊢ ∃ x, x ≠ 0 ∧ I' = Ideal.span {x}
Module: Mathlib.RingTheory.ClassGroup.Basic

Goal state before:
pp: R : Type u_1
K : Type u_2
inst✝⁵ : CommRing R
inst✝⁴ : Field K
inst✝³ : Algebra R K
inst✝² : IsFractionRing R K
inst✝¹ : IsDomain R
inst✝ : IsDedekindDomain R
I : ↥(Ideal R)⁰
⊢ (equiv K) (mk0 I) = (QuotientGroup.mk' (toPrincipalIdeal R K).range) ((FractionalIdeal.mk0 K) I)

Tactic:
rw [ClassGroup.mk0, MonoidHom.comp_apply, ClassGroup.equiv_mk]
  congr 1
  simp [← Units.val_inj]

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

Goal state before:
pp: case h
R : Type u_1
K : Type u_2
inst✝⁹ : CommRing R
inst✝⁸ : Field K
inst✝⁷ : Algebra R K
inst✝⁶ : IsFractionRing R K
inst✝⁵ : IsDomain R
S : Type u_3
L : Type u_4
inst✝⁴ : CommRing S
inst✝³ : IsDomain S
inst✝² : Field L
inst✝¹ : Algebra S L
inst✝ : IsFractionRing S L
f : R ≃+* S
I : (FractionalIdeal S⁰ L)ˣ
x✝ : ∃ x, spanSingleton S⁰ ↑x = ↑I
u : Lˣ
hu : spanSingleton S⁰ ↑u = ↑I
⊢ (ringEquivOfRingEquiv L K f.symm) (spanSingleton S⁰ ↑u) = (↑(ringEquivOfRingEquiv K L f)).symm ↑I

Tactic:
← FractionalIdeal.ringEquivOfRingEquiv_symm_eq,

Goal state after:
case h
R : Type u_1
K : Type u_2
inst✝⁹ : CommRing R
inst✝⁸ : Field K
inst✝⁷ : Algebra R K
inst✝⁶ : IsFractionRing R K
inst✝⁵ : IsDomain R
S : Type u_3
L : Type u_4
inst✝⁴ : CommRing S
inst✝³ : IsDomain S
inst✝² : Field L
inst✝¹ : Algebra S L
inst✝ : IsFractionRing S L
f : R ≃+* S
I : (FractionalIdeal S⁰ L)ˣ
x✝ : ∃ x, spanSingleton S⁰ ↑x = ↑I
u : Lˣ
hu : spanSingleton S⁰ ↑u = ↑I
⊢ (ringEquivOfRingEquiv K L f).symm (spanSingleton S⁰ ↑u) = (↑(ringEquivOfRingEquiv K L f)).symm ↑I