mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: case h2
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
⊢ ∀ (x : (Q.comp P).toExtension.Cotangent),
    (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) x = 0 →
      x ∈ (LinearMap.liftBaseChange T (Extension.Cotangent.map (Q.toComp P).toExtensionHom)).range

Tactic:
intro x hx
    obtain ⟨⟨x : (Q.comp P).Ring, hx'⟩, rfl⟩ := Extension.Cotangent.mk_surjective x
    replace hx : (Q.ofComp P).toAlgHom x ∈ Q.ker ^ 2 := by
      simpa only [map_mk, val_mk, val_zero, Ideal.toCotangent_eq_zero] using! congr(($hx).val)
    rw [pow_two, ← map_ofComp_ker (P := P), ← Ideal.map_mul, Ideal.mem_map_iff_of_surjective
      _ (toAlgHom_ofComp_surjective Q P)] at hx
    obtain ⟨y, hy, e⟩ := hx
    rw [eq_comm, ← sub_eq_zero, ← map_sub, ← RingHom.mem_ker, ← map_toComp_ker] at e
    rw [LinearMap.range_liftBaseChange]
    let z : (Q.comp P).ker := ⟨x - y, Ideal.sub_mem _ hx' (Ideal.mul_le_right hy)⟩
    have hz : z.1 ∈ P.ker.map (Q.toComp P).toAlgHom.toRingHom := e
    have : Extension.Cotangent.mk (P := (Q.comp P).toExtension) ⟨x, hx'⟩ =
      Extension.Cotangent.mk z := by
      ext; simpa only [val_mk, Ideal.toCotangent_eq, sub_sub_cancel, pow_two, z]
    rw [this, ← Submodule.restrictScalars_mem (Q.comp P).Ring, ← Submodule.mem_comap,
      ← Submodule.span_singleton_le_iff_mem, ← Submodule.map_le_map_iff_of_injective
      (f := Submodule.subtype _) Subtype.val_injective, Submodule.map_subtype_span_singleton,
      Submodule.span_singleton_le_iff_mem]
    refine (show Ideal.map (Q.toComp P).toAlgHom.toRingHom P.ker ≤ _ from ?_) hz
    rw [Ideal.map_le_iff_le_comap]
    rintro w hw
    simp only [AlgHom.toRingHom_eq_coe, Ideal.mem_comap, RingHom.coe_coe,
      Submodule.mem_map, Submodule.mem_comap, Submodule.restrictScalars_mem, Submodule.coe_subtype,
      Subtype.exists, exists_and_right, exists_eq_right,
      toExtension_Ring]
    refine ⟨?_, Submodule.subset_span ⟨Extension.Cotangent.mk ⟨w, hw⟩, ?_⟩⟩
    · simp only [ker_eq_ker_aeval_val, RingHom.mem_ker, Hom.algebraMap_toAlgHom]
      rw [aeval_val_eq_zero hw, map_zero]
    · rw [map_mk]
      rfl

Goal state after:
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
g : S →ₐ[R] P
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hg : (IsScalarTower.toAlgHom R P S).comp g = AlgHom.id R S
⊢ retractionOfSectionOfKerSqZero g hf' hg ∘ₗ kerToTensor R P S = LinearMap.id

Tactic:
ext x

Goal state after:
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
g : S →ₐ[R] P
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hg : (IsScalarTower.toAlgHom R P S).comp g = AlgHom.id R S
x : ↥(RingHom.ker (algebraMap P S))
⊢ ↑((retractionOfSectionOfKerSqZero g hf' hg ∘ₗ kerToTensor R P S) x) = ↑(LinearMap.id x)
Module: Mathlib.RingTheory.Unramified.Field

Goal state before:
pp: K : Type u_1
L : Type u_3
inst✝⁵ : Field K
inst✝⁴ : Field L
inst✝³ : Algebra K L
inst✝² : Algebra.IsSeparable K L
B : Type u_3
inst✝¹ : CommRing B
inst✝ : Algebra K B
I : Ideal B
hI : I ^ 2 = ⊥
f₁ f₂ : L →ₐ[K] B
e : (Ideal.Quotient.mkₐ K I).comp f₁ = (Ideal.Quotient.mkₐ K I).comp f₂
⊢ f₁ = f₂

Tactic:
ext x

Goal state after:
K : Type u_1
L : Type u_3
inst✝⁵ : Field K
inst✝⁴ : Field L
inst✝³ : Algebra K L
inst✝² : Algebra.IsSeparable K L
B : Type u_3
inst✝¹ : CommRing B
inst✝ : Algebra K B
I : Ideal B
hI : I ^ 2 = ⊥
f₁ f₂ : L →ₐ[K] B
e : (Ideal.Quotient.mkₐ K I).comp f₁ = (Ideal.Quotient.mkₐ K I).comp f₂
x : L
⊢ f₁ x = f₂ x
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
⊢ LinearMap.liftBaseChange T (Extension.CotangentSpace.map (Q.toComp P).toExtensionHom) ∘ₗ
      LinearMap.baseChange T P.toExtension.cotangentComplex =
    (Q.comp P).toExtension.cotangentComplex ∘ₗ
      LinearMap.liftBaseChange T (Extension.Cotangent.map (Q.toComp P).toExtensionHom)

Tactic:
ext x

Goal state after:
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : P.toExtension.Cotangent
⊢ ((AlgebraTensorModule.curry
          (LinearMap.liftBaseChange T (Extension.CotangentSpace.map (Q.toComp P).toExtensionHom) ∘ₗ
            LinearMap.baseChange T P.toExtension.cotangentComplex))
        1)
      x =
    ((AlgebraTensorModule.curry
          ((Q.comp P).toExtension.cotangentComplex ∘ₗ
            LinearMap.liftBaseChange T (Extension.Cotangent.map (Q.toComp P).toExtensionHom)))
        1)
      x
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
l : S ⊗[P] Ω[P⁄R] →ₗ[P] ↥(RingHom.ker (algebraMap P S))
hl : l ∘ₗ kerToTensor R P S = LinearMap.id
σ : S → P
hσ : ∀ (x : S), (algebraMap P S) (σ x) = x
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
⊢ (IsScalarTower.toAlgHom R P S).comp (sectionOfRetractionKerToTensorAux l hl σ hσ hf') = AlgHom.id R S

Tactic:
ext x

Goal state after:
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
l : S ⊗[P] Ω[P⁄R] →ₗ[P] ↥(RingHom.ker (algebraMap P S))
hl : l ∘ₗ kerToTensor R P S = LinearMap.id
σ : S → P
hσ : ∀ (x : S), (algebraMap P S) (σ x) = x
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
x : S
⊢ ((IsScalarTower.toAlgHom R P S).comp (sectionOfRetractionKerToTensorAux l hl σ hσ hf')) x = (AlgHom.id R S) x
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: case e_6
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : ↥Q.ker
hx : Extension.Cotangent.mk x ∈ Q.toExtension.cotangentComplex.ker
y : (Q.comp P).toExtension.Cotangent := Extension.Cotangent.mk (Q.kerCompPreimage P x)
⊢ (Q.ofComp P).toExtensionHom.toAlgHom ↑(Q.kerCompPreimage P x) = ↑x

Tactic:
exact ofComp_kerCompPreimage Q P x

Goal state after:
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : ↥Q.ker
hx : Extension.Cotangent.mk x ∈ Q.toExtension.cotangentComplex.ker
y : (Q.comp P).toExtension.Cotangent := Extension.Cotangent.mk (Q.kerCompPreimage P x)
hy : (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) y = Extension.Cotangent.mk x
z : T ⊗[S] P.toExtension.CotangentSpace :=
  ((CotangentSpace.compEquiv Q P) ((Q.comp P).toExtension.cotangentComplex y)).2
⊢ (δ Q P) ⟨Extension.Cotangent.mk x, hx⟩ = (δAux R Q) ↑x

Tactic:
H1Cotangent.δ_eq (y := y) (z := z)

Goal state after:
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : ↥Q.ker
hx : Extension.Cotangent.mk x ∈ Q.toExtension.cotangentComplex.ker
y : (Q.comp P).toExtension.Cotangent := Extension.Cotangent.mk (Q.kerCompPreimage P x)
hy : (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) y = Extension.Cotangent.mk x
z : T ⊗[S] P.toExtension.CotangentSpace :=
  ((CotangentSpace.compEquiv Q P) ((Q.comp P).toExtension.cotangentComplex y)).2
⊢ (LinearMap.baseChange T P.toExtension.toKaehler) z = (δAux R Q) ↑x

case hy
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : ↥Q.ker
hx : Extension.Cotangent.mk x ∈ Q.toExtension.cotangentComplex.ker
y : (Q.comp P).toExtension.Cotangent := Extension.Cotangent.mk (Q.kerCompPreimage P x)
hy : (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) y = Extension.Cotangent.mk x
z : T ⊗[S] P.toExtension.CotangentSpace :=
  ((CotangentSpace.compEquiv Q P) ((Q.comp P).toExtension.cotangentComplex y)).2
⊢ (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) y = ↑⟨Extension.Cotangent.mk x, hx⟩

case hz
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : ↥Q.ker
hx : Extension.Cotangent.mk x ∈ Q.toExtension.cotangentComplex.ker
y : (Q.comp P).toExtension.Cotangent := Extension.Cotangent.mk (Q.kerCompPreimage P x)
hy : (Extension.Cotangent.map (Q.ofComp P).toExtensionHom) y = Extension.Cotangent.mk x
z : T ⊗[S] P.toExtension.CotangentSpace :=
  ((CotangentSpace.compEquiv Q P) ((Q.comp P).toExtension.cotangentComplex y)).2
⊢ (LinearMap.liftBaseChange T (Extension.CotangentSpace.map (Q.toComp P).toExtensionHom)) z =
    (Q.comp P).toExtension.cotangentComplex y
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
⊢ kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁

Tactic:
ext x

Goal state after:
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
x : (RingHom.ker (algebraMap P S)).Cotangent
⊢ (kerCotangentToTensor R P S) x = (↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁) x
Module: Mathlib.RingTheory.Unramified.Field

Goal state before:
pp: K : Type u_1
A : Type u_2
inst✝⁴ : Field K
inst✝³ : CommRing A
inst✝² : Algebra K A
inst✝¹ : FormallyUnramified K A
inst✝ : EssFiniteType K A
x : A
hx : IsNilpotent x
f : A →ₐ[K] AlgebraicClosure K ⊗[K] A := TensorProduct.includeRight
⊢ ⇑f = ⇑(LinearMap.rTensor A (ofId K (AlgebraicClosure K)).toLinearMap ∘ₗ (TensorProduct.lid K A).symm.toLinearMap)

Tactic:
ext x

Goal state after:
K : Type u_1
A : Type u_2
inst✝⁴ : Field K
inst✝³ : CommRing A
inst✝² : Algebra K A
inst✝¹ : FormallyUnramified K A
inst✝ : EssFiniteType K A
x✝ : A
hx : IsNilpotent x✝
f : A →ₐ[K] AlgebraicClosure K ⊗[K] A := TensorProduct.includeRight
x : A
⊢ f x = (LinearMap.rTensor A (ofId K (AlgebraicClosure K)).toLinearMap ∘ₗ (TensorProduct.lid K A).symm.toLinearMap) x
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: case refine_3
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
x✝ : { l // l ∘ₗ kerToTensor R P' S = LinearMap.id }
l : S ⊗[P'] Ω[P'⁄R] →ₗ[P'] ↥(RingHom.ker (algebraMap P' S))
hl : l ∘ₗ kerToTensor R P' S = LinearMap.id
⊢ (↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm) ∘ₗ kerCotangentToTensor R P S = LinearMap.id

Tactic:
ext x

Goal state after:
case refine_3
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
x✝ : { l // l ∘ₗ kerToTensor R P' S = LinearMap.id }
l : S ⊗[P'] Ω[P'⁄R] →ₗ[P'] ↥(RingHom.ker (algebraMap P' S))
hl : l ∘ₗ kerToTensor R P' S = LinearMap.id
x : (RingHom.ker (algebraMap P S)).Cotangent
⊢ ((↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm) ∘ₗ kerCotangentToTensor R P S) x = LinearMap.id x
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: case hF
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
⊢ Extension.Cotangent.map (Q.ofComp P).toExtensionHom ∘ₗ Extension.h1Cotangentι =
    Extension.h1Cotangentι ∘ₗ Extension.H1Cotangent.map (Q.ofComp P).toExtensionHom

Tactic:
ext x

Goal state after:
case hF
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
σ : Type w₂
Q : Generators S T ι
P : Generators R S σ
x : (Q.comp P).toExtension.H1Cotangent
⊢ ((Extension.Cotangent.map (Q.ofComp P).toExtensionHom ∘ₗ Extension.h1Cotangentι) x).val =
    ((Extension.h1Cotangentι ∘ₗ Extension.H1Cotangent.map (Q.ofComp P).toExtensionHom) x).val
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: case refine_4
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
f : { l // l ∘ₗ kerCotangentToTensor R P S = LinearMap.id }
⊢ (fun x ↦
        match x with
        | ⟨l, hl⟩ => ⟨↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm, ⋯⟩)
      ((fun x ↦
          match x with
          | ⟨l, hl⟩ => ⟨{ toAddHom := ↑(↑e₁ ∘ₗ l ∘ₗ ↑e₂), map_smul' := ⋯ }, ⋯⟩)
        f) =
    f

Tactic:
ext x

Goal state after:
case refine_4
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
f : { l // l ∘ₗ kerCotangentToTensor R P S = LinearMap.id }
x : S
a✝ : P
⊢ (((AlgebraTensorModule.curry
              ↑((fun x ↦
                    match x with
                    | ⟨l, hl⟩ => ⟨↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm, ⋯⟩)
                  ((fun x ↦
                      match x with
                      | ⟨l, hl⟩ => ⟨{ toAddHom := ↑(↑e₁ ∘ₗ l ∘ₗ ↑e₂), map_smul' := ⋯ }, ⋯⟩)
                    f)))
            x).compDer
        (D R P))
      a✝ =
    (((AlgebraTensorModule.curry ↑f) x).compDer (D R P)) a✝
Module: Mathlib.RingTheory.Kaehler.JacobiZariski

Goal state before:
pp: R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
ι' : Type w₃
σ : Type w₂
σ' : Type w₄
Q : Generators S T ι
P : Generators R S σ
Q' : Generators S T ι'
P' : Generators R S σ'
⊢ δ Q P ∘ₗ ↑(equiv Q' Q) = δ Q' P'

Tactic:
ext x

Goal state after:
R : Type u₁
S : Type u₂
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u₃
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Algebra S T
inst✝ : IsScalarTower R S T
ι : Type w₁
ι' : Type w₃
σ : Type w₂
σ' : Type w₄
Q : Generators S T ι
P : Generators R S σ
Q' : Generators S T ι'
P' : Generators R S σ'
x : Q'.toExtension.H1Cotangent
⊢ (δ Q P ∘ₗ ↑(equiv Q' Q)) x = (δ Q' P') x
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: case refine_5
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := P ⧸ RingHom.ker (algebraMap P S) ^ 2
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) :=
  (RingHom.ker (algebraMap P S)).cotangentEquivIdeal ≪≫ₗ
    LinearEquiv.restrictScalars P
      (LinearEquiv.ofEq (RingHom.ker (IsScalarTower.toAlgHom R P S).toRingHom).cotangentIdeal
        (RingHom.ker (IsScalarTower.toAlgHom R P S).kerSquareLift.toRingHom) ⋯)
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := LinearEquiv.restrictScalars P (tensorKaehlerQuotKerSqEquiv R P S)
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
f : { l // l ∘ₗ kerToTensor R P' S = LinearMap.id }
⊢ (fun x ↦
        match x with
        | ⟨l, hl⟩ => ⟨{ toAddHom := ↑(↑e₁ ∘ₗ l ∘ₗ ↑e₂), map_smul' := ⋯ }, ⋯⟩)
      ((fun x ↦
          match x with
          | ⟨l, hl⟩ => ⟨↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm, ⋯⟩)
        f) =
    f

Tactic:
ext x

Goal state after:
case refine_5
R : Type u_1
P : Type u_2
S : Type u_3
inst✝⁶ : CommRing R
inst✝⁵ : CommRing P
inst✝⁴ : CommRing S
inst✝³ : Algebra R P
inst✝² : Algebra P S
inst✝¹ : Algebra R S
inst✝ : IsScalarTower R P S
hf' : RingHom.ker (algebraMap P S) ^ 2 = ⊥
hf : Surjective ⇑(algebraMap P S)
P' : Type u_2 := ⋯
h₁ : Surjective ⇑(algebraMap P' S)
h₂ : RingHom.ker (algebraMap P' S) ^ 2 = ⊥
e₁ : (RingHom.ker (algebraMap P S)).Cotangent ≃ₗ[P] ↥(RingHom.ker (algebraMap P' S)) := ⋯
e₂ : S ⊗[P'] Ω[P'⁄R] ≃ₗ[P] S ⊗[P] Ω[P⁄R] := ⋯
H : kerCotangentToTensor R P S = ↑e₂ ∘ₗ ↑P (kerToTensor R P' S) ∘ₗ ↑e₁
f : { l // l ∘ₗ kerToTensor R P' S = LinearMap.id }
x : S
a✝ : P'
⊢ ↑((((AlgebraTensorModule.curry
                ↑((fun x ↦
                      match x with
                      | ⟨l, hl⟩ => ⟨{ toAddHom := ↑(↑e₁ ∘ₗ l ∘ₗ ↑e₂), map_smul' := ⋯ }, ⋯⟩)
                    ((fun x ↦
                        match x with
                        | ⟨l, hl⟩ => ⟨↑e₁.symm ∘ₗ ↑P l ∘ₗ ↑e₂.symm, ⋯⟩)
                      f)))
              x).compDer
          (D R P'))
        a✝) =
    ↑((((AlgebraTensorModule.curry ↑f) x).compDer (D R P')) a✝)
Module: Mathlib.RingTheory.Smooth.Kaehler

Goal state before:
pp: case left
R : Type u_1
S : Type u_3
inst✝² : CommRing R
inst✝¹ : CommRing S
inst✝ : Algebra R S
P : Extension R S
⊢ Function.Injective ⇑(map P.toInfinitesimal)

Tactic:
intro x y e
    ext1
    exact (Cotangent.map_toInfinitesimal_bijective P).1 (congr_arg Subtype.val e)

Goal state after: