mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.RingTheory.Polynomial.Resultant.Basic

Goal state before:
pp: case surjective
R✝ : Type u_1
inst✝² : CommRing R✝
R S : Type u_1
inst✝¹ : CommRing R
inst✝ : CommRing S
φ : R →+* S
hφ : Function.Surjective ⇑φ
f : S[X]
IH :
  ∀ (q g₁ g₂ : R[X]), q.resultant (g₁ * g₂) q.natDegree (g₁.natDegree + g₂.natDegree) = q.resultant g₁ * q.resultant g₂
g₁ g₂ : S[X]
f' : R[X]
hf' : map φ f' = f
e : f'.degree = f.degree
g₁' : R[X]
hg₁ : map φ g₁' = g₁
e₁ : g₁'.degree = g₁.degree
g₂' : R[X]
hg₂ : map φ g₂' = g₂
e₂ : g₂'.degree = g₂.degree
⊢ φ (f'.resultant (g₁' * g₂') (map φ f').natDegree (g₁.natDegree + (map φ g₂').natDegree)) =
    φ (f'.resultant g₁' (map φ f').natDegree g₁.natDegree) *
      φ (f'.resultant g₂' (map φ f').natDegree (map φ g₂').natDegree)

Tactic:
hg₂,

Goal state after:
case surjective
R✝ : Type u_1
inst✝² : CommRing R✝
R S : Type u_1
inst✝¹ : CommRing R
inst✝ : CommRing S
φ : R →+* S
hφ : Function.Surjective ⇑φ
f : S[X]
IH :
  ∀ (q g₁ g₂ : R[X]), q.resultant (g₁ * g₂) q.natDegree (g₁.natDegree + g₂.natDegree) = q.resultant g₁ * q.resultant g₂
g₁ g₂ : S[X]
f' : R[X]
hf' : map φ f' = f
e : f'.degree = f.degree
g₁' : R[X]
hg₁ : map φ g₁' = g₁
e₁ : g₁'.degree = g₁.degree
g₂' : R[X]
hg₂ : map φ g₂' = g₂
e₂ : g₂'.degree = g₂.degree
⊢ φ (f'.resultant (g₁' * g₂') (map φ f').natDegree (g₁.natDegree + g₂.natDegree)) =
    φ (f'.resultant g₁' (map φ f').natDegree g₁.natDegree) * φ (f'.resultant g₂' (map φ f').natDegree g₂.natDegree)
Module: Mathlib.RingTheory.Polynomial.UniversalFactorizationRing

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
n m k : ℕ
hn : n = m + k
this : Algebra (MvPolynomial (Fin n) R) (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R) :=
  (universalFactorizationMap R n m k hn).toAlgebra
⊢ (universalFactorizationMap R n m k hn).IsIntegral

Tactic:
have : IsDomain (MvPolynomial (Fin m) ℤ ⊗[ℤ] MvPolynomial (Fin k) ℤ) :=
    (MvPolynomial.tensorEquivSum ℤ (Fin m) (Fin k) ℤ).toRingEquiv.isDomain_iff.mpr inferInstance

Goal state after:
R : Type u_1
inst✝ : CommRing R
n m k : ℕ
hn : n = m + k
this✝ : Algebra (MvPolynomial (Fin n) R) (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R) :=
  (universalFactorizationMap R n m k hn).toAlgebra
this : IsDomain (MvPolynomial (Fin m) ℤ ⊗[ℤ] MvPolynomial (Fin k) ℤ)
⊢ (universalFactorizationMap R n m k hn).IsIntegral
Module: Mathlib.RingTheory.Polynomial.UniversalFactorizationRing

Goal state before:
pp: case refine_2
R : Type u_1
S : Type u_2
T : Type u_3
inst✝⁴ : CommRing R
inst✝³ : CommRing S
inst✝² : CommRing T
inst✝¹ : Algebra R S
inst✝ : Algebra R T
n m k : ℕ
hn : n = m + k
p : MonicDegreeEq R n
f : failed to pretty print expression (use 'set_option pp.rawOnError true' for raw representation)
this✝³ : Algebra (MvPolynomial (Fin n) R) (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R) :=
  (MvPolynomial.universalFactorizationMap R n m k hn).toAlgebra
this✝² : Algebra (MvPolynomial (Fin n) R) R := ((MvPolynomial.mapEquivMonic R R n).symm p).toAlgebra
this✝¹ : Algebra (MvPolynomial (Fin n) R) S := Algebra.compHom S ((MvPolynomial.mapEquivMonic R R n).symm p).toRingHom
this✝ : IsScalarTower (MvPolynomial (Fin n) R) R S
this : IsScalarTower R (MvPolynomial (Fin n) R) S
⊢ (AlgHom.restrictScalars R
          (AlgHom.restrictScalars R
            ((AlgHom.restrictScalars (MvPolynomial (Fin n) R)
                  ((fun q ↦
                      Algebra.TensorProduct.lift (Algebra.ofId R S)
                        (let __RingHom :=
                          (↑((MvPolynomial.universalFactorizationMapLiftEquiv R S n m k hn
                                    (p.map (algebraMap R S))).symm
                                q)).toRingHom;
                        { toRingHom := __RingHom, commutes' := ⋯ })
                        ⋯)
                    ((fun f ↦ ⟨((factor₁ m k hn p).map ↑f, (factor₂ m k hn p).map ↑f), ⋯⟩) f))).comp
              Algebra.TensorProduct.includeRight))).comp
      Algebra.TensorProduct.includeRight =
    (AlgHom.restrictScalars R
          (AlgHom.restrictScalars R
            ((AlgHom.restrictScalars (MvPolynomial (Fin n) R) f).comp Algebra.TensorProduct.includeRight))).comp
      Algebra.TensorProduct.includeRight

Tactic:
ext; simp [MvPolynomial.universalFactorizationMapLiftEquiv, MvPolynomial.mapEquivMonic,
        UniversalFactorizationRing.factor₂, coeff_freeMonic]; rfl

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

Goal state before:
pp: case inr.inr.inr
R : Type u_1
inst✝ : CommRing R
n m k : ℕ
hn : n = m + k
p : MonicDegreeEq R n
h✝² : Nontrivial 𝓡
h✝¹ : Nontrivial (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R)
h✝ : Nontrivial R
this✝ : Algebra (MvPolynomial (Fin n) R) (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R) :=
  (MvPolynomial.universalFactorizationMap R n m k hn).toAlgebra
this : Algebra (MvPolynomial (Fin n) R) R := ((MvPolynomial.mapEquivMonic R R n).symm p).toAlgebra
⊢ (-1) ^ n *
      (map ((↑(fromTensor m k hn p)).comp Algebra.TensorProduct.includeLeftRingHom) (freeMonic R m)).resultant
        (map ((↑(fromTensor m k hn p)).comp Algebra.TensorProduct.includeRight.toRingHom) (freeMonic R k))
        (map Algebra.TensorProduct.includeLeftRingHom (freeMonic R m)).natDegree
        (map Algebra.TensorProduct.includeRight.toRingHom (freeMonic R k)).natDegree =
    (-1) ^ n * (↑(factor₁ m k hn p)).resultant ↑(factor₂ m k hn p)

Tactic:
(monic_freeMonic R k).natDegree_map,

Goal state after:
case inr.inr.inr
R : Type u_1
inst✝ : CommRing R
n m k : ℕ
hn : n = m + k
p : MonicDegreeEq R n
h✝² : Nontrivial 𝓡
h✝¹ : Nontrivial (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R)
h✝ : Nontrivial R
this✝ : Algebra (MvPolynomial (Fin n) R) (MvPolynomial (Fin m) R ⊗[R] MvPolynomial (Fin k) R) :=
  (MvPolynomial.universalFactorizationMap R n m k hn).toAlgebra
this : Algebra (MvPolynomial (Fin n) R) R := ((MvPolynomial.mapEquivMonic R R n).symm p).toAlgebra
⊢ (-1) ^ n *
      (map ((↑(fromTensor m k hn p)).comp Algebra.TensorProduct.includeLeftRingHom) (freeMonic R m)).resultant
        (map ((↑(fromTensor m k hn p)).comp Algebra.TensorProduct.includeRight.toRingHom) (freeMonic R k))
        (map Algebra.TensorProduct.includeLeftRingHom (freeMonic R m)).natDegree (freeMonic R k).natDegree =
    (-1) ^ n * (↑(factor₁ m k hn p)).resultant ↑(factor₂ m k hn p)
Module: Mathlib.RingTheory.Polynomial.UniversalFactorizationRing

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
n m k : ℕ
hn : n = m + k
p : MonicDegreeEq R n
P : Ideal R
inst✝ : P.IsPrime
f : MonicDegreeEq P.ResidueField m
g : MonicDegreeEq P.ResidueField k
H✝ : map (algebraMap R P.ResidueField) ↑p = ↑f * ↑g
Hpq : IsCoprime ↑f ↑g
φ : 𝓡' →ₐ[R] P.ResidueField := ⋯
Q : Ideal 𝓡' := ⋯
this✝ : Q.IsPrime
this : Q.LiesOver P
φ' : Q.ResidueField →ₐ[R] P.ResidueField := ⋯
φi : P.ResidueField →ₐ[R] Q.ResidueField := ⋯
e : P.ResidueField ≃ₐ[R] Q.ResidueField := ⋯
H : φi.comp φ = IsScalarTower.toAlgHom R 𝓡' Q.ResidueField
⊢ (↑((homEquiv Q.ResidueField m k hn p) (φi.comp φ))).1 = (factor₁ m k hn p).map (algebraMap 𝓡' Q.ResidueField)

Tactic:
· rw [H]
      simp [homEquiv, UniversalFactorizationRing.homEquiv, factor₁,
        MonicDegreeEq.map, Polynomial.map_map]
      rfl

Goal state after:
Module: Mathlib.AlgebraicGeometry.Group.Abelian

Goal state before:
pp: case refine_3.refine_2
K : Type u
inst✝⁴ : Field K
inst✝³ : IsAlgClosed K
G : Over (Spec (CommRingCat.of K))
inst✝² : IsProper G.hom
inst✝¹ : IsIntegral (G ⊗ G).left
inst✝ : GrpObj G
S : Scheme := Spec (CommRingCat.of K)
point : ↥S := IsLocalRing.closedPoint K
hpoint : IsClosed {point}
this✝⁹ : Nonempty ↥G.left
this✝⁸ : IsProper (G ⊗ G).hom
this✝⁷ : JacobsonSpace ↥(G ⊗ G).left
this✝⁶ : Surjective G.hom
this✝⁵ : IsProper (Over.Hom.left (fst G G))
this✝⁴ : Surjective (Over.Hom.left (fst G G))
this✝³ : IsProper (Over.Hom.left (GrpObj.commutator G) ≫ G.hom)
this✝² : IsClosedImmersion (Over.Hom.left (lift η η) ≫ Over.Hom.left (fst G G))
this✝¹ : IsClosedImmersion (Over.Hom.left (lift η η))
γ : G ⊗ G ⟶ G ⊗ G := lift (fst G G) (GrpObj.commutator G)
this✝ : IsProper (Over.Hom.left γ ≫ Over.Hom.left (fst G G))
this : IsProper (Over.Hom.left γ)
H✝¹ :
  ⇑(Over.Hom.left γ) '' ⇑(Over.Hom.left (fst G G)) ⁻¹' {(Over.Hom.left η) point} ⊆ {(Over.Hom.left (lift η η)) point}
U : G.left.Opens
hηU : (Over.Hom.left η) point ∈ U
H✝ : IsFinite ((Scheme.Hom.imageι (Over.Hom.left γ) ≫ Over.Hom.left (fst G G)) ∣_ U)
H : ∀ (x : ↥U), (⇑(pullback.fst G.hom G.hom) ⁻¹' {↑x} ∩ Set.range ⇑(Over.Hom.left γ)).Finite
y : ↥(G ⊗ G).left
hyU : y ∈ ↑(Over.Hom.left (fst G G) ⁻¹ᵁ U)
hy : IsClosed {y}
hx : IsClosed {(Over.Hom.left (fst G G)) y}
x : 𝟙_ (Over (Spec (CommRingCat.of K))) ⟶ G := Over.homMk (pointOfClosedPoint G.hom ((Over.Hom.left (fst G G)) y) hx) ⋯
xe : ↥(G ⊗ G).left := (Over.Hom.left (fst G G ≫ (ρ_ G).inv ≫ G ◁ η)) y
⊢ (Over.Hom.left γ) xe = xe

Tactic:
simp only [xe, γ, ← Scheme.Hom.comp_apply, ← Over.comp_left]
          congr 6; ext <;> simp

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

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u_3
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Module.FaithfullyFlat R T
inst✝ : FiniteType T (T ⊗[R] S)
s : Finset (T ⊗[R] S)
hs : adjoin T ↑s = ⊤
k : ↥s → ℕ
t : (x : ↥s) → Fin (k x) → T
m : (x : ↥s) → Fin (k x) → S
h : ∀ (x : ↥s), ↑x = ∑ j, t x j ⊗ₜ[R] m x j
⊢ FiniteType R S

Tactic:
let f : MvPolynomial (Σ x : s, Fin (k x)) R →ₐ[R] S := MvPolynomial.aeval (fun ⟨x, i⟩ ↦ m x i)

Goal state after:
R : Type u_1
S : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u_3
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Module.FaithfullyFlat R T
inst✝ : FiniteType T (T ⊗[R] S)
s : Finset (T ⊗[R] S)
hs : adjoin T ↑s = ⊤
k : ↥s → ℕ
t : (x : ↥s) → Fin (k x) → T
m : (x : ↥s) → Fin (k x) → S
h : ∀ (x : ↥s), ↑x = ∑ j, t x j ⊗ₜ[R] m x j
f : MvPolynomial ((x : ↥s) × Fin (k x)) R →ₐ[R] S :=
  MvPolynomial.aeval fun x ↦
    match x with
    | ⟨x, i⟩ => m x i
⊢ FiniteType R S
Module: Mathlib.AlgebraicGeometry.ZariskisMainTheorem

Goal state before:
pp: case refine_2
X Y : Scheme
f : X ⟶ Y
inst✝ : IsProper f
y : ↥Y
hx : (⇑f ⁻¹' {y}).Finite
V : Y.Opens := { carrier := (⇑f '' (↑(Scheme.Hom.quasiFiniteLocus f))ᶜ)ᶜ, is_open' := ⋯ }
x : ↥↑(f ⁻¹ᵁ V)
this : Scheme.Hom.QuasiFiniteAt f ((f ⁻¹ᵁ V).ι x)
⊢ x ∈ ↑(Scheme.Hom.quasiFiniteLocus (f ∣_ V)) ↔ x ∈ ↑⊤

Tactic:
rw [← Scheme.Hom.quasiFiniteAt_comp_iff_of_isOpenImmersion, ← morphismRestrict_ι,
      Scheme.Hom.quasiFiniteAt_comp_iff] at this

Goal state after:
case refine_2
X Y : Scheme
f : X ⟶ Y
inst✝ : IsProper f
y : ↥Y
hx : (⇑f ⁻¹' {y}).Finite
V : Y.Opens := { carrier := (⇑f '' (↑(Scheme.Hom.quasiFiniteLocus f))ᶜ)ᶜ, is_open' := ⋯ }
x : ↥↑(f ⁻¹ᵁ V)
this : Scheme.Hom.QuasiFiniteAt (f ∣_ V) x
⊢ x ∈ ↑(Scheme.Hom.quasiFiniteLocus (f ∣_ V)) ↔ x ∈ ↑⊤
Module: Mathlib.RingTheory.Etale.Descent

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u_3
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Module.FaithfullyFlat R T
inst✝ : FormallyUnramified T (T ⊗[R] S)
x✝ : Algebra S (T ⊗[R] S) := TensorProduct.rightAlgebra
⊢ Subsingleton Ω[S⁄R]

Tactic:
have : Subsingleton (T ⊗[R] Ω[S⁄R]) :=
    (KaehlerDifferential.tensorKaehlerEquivBase R T S (T ⊗[R] S)).subsingleton

Goal state after:
R : Type u_1
S : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u_3
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Module.FaithfullyFlat R T
inst✝ : FormallyUnramified T (T ⊗[R] S)
x✝ : Algebra S (T ⊗[R] S) := TensorProduct.rightAlgebra
this : Subsingleton (T ⊗[R] Ω[S⁄R])
⊢ Subsingleton Ω[S⁄R]
Module: Mathlib.RingTheory.Etale.Descent

Goal state before:
pp: R : Type u_1
S : Type u_2
inst✝⁶ : CommRing R
inst✝⁵ : CommRing S
inst✝⁴ : Algebra R S
T : Type u_3
inst✝³ : CommRing T
inst✝² : Algebra R T
inst✝¹ : Module.FaithfullyFlat R T
inst✝ : FormallyUnramified T (T ⊗[R] S)
⊢ FormallyUnramified R S

Tactic:
by
  constructor
  let _ : Algebra S (T ⊗[R] S) := TensorProduct.rightAlgebra
  have : Subsingleton (T ⊗[R] Ω[S⁄R]) :=
    (KaehlerDifferential.tensorKaehlerEquivBase R T S (T ⊗[R] S)).subsingleton
  exact Module.FaithfullyFlat.lTensor_reflects_triviality R T _

Goal state after:
Module: Mathlib.AlgebraicGeometry.IdealSheaf.IrreducibleComponent

Goal state before:
pp: X : Scheme
Z : Set ↥X
hZ : Z ∈ irreducibleComponents ↥X
inst✝ : IsNoetherian X
⊢ X.irreducibleComponentIdeal Z hZ = Hom.ker (X.irreducibleComponentOpen Z).ι

Tactic:
by
  ext
  rfl

Goal state after:
Module: Mathlib.AlgebraicGeometry.Morphisms.FlatRank

Goal state before:
pp: X Y Z : Scheme
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : Flat f
inst✝ : IsFinite f
R : CommRingCat
i : Spec R ⟶ Y
w✝ : IsOpenImmersion i
y' : ↥(Spec R)
⊢ IsAffine.finrank (pullback.snd (pullback.snd f g) i) y' = IsAffine.finrank (pullback.snd f (i ≫ g)) y'

Tactic:
← pullbackLeftPullbackSndIso_hom_snd f g i,

Goal state after:
X Y Z : Scheme
f : X ⟶ Z
g : Y ⟶ Z
inst✝¹ : Flat f
inst✝ : IsFinite f
R : CommRingCat
i : Spec R ⟶ Y
w✝ : IsOpenImmersion i
y' : ↥(Spec R)
⊢ IsAffine.finrank ((pullbackLeftPullbackSndIso f g i).hom ≫ pullback.snd f (i ≫ g)) y' =
    IsAffine.finrank (pullback.snd f (i ≫ g)) y'
Module: Mathlib.AlgebraicGeometry.Morphisms.FlatRank

Goal state before:
pp: R S : CommRingCat
x : ↥(Spec S)
φ : R ⟶ S
inst✝¹ : Flat (Spec.map φ)
inst✝ : IsFinite (Spec.map φ)
⊢ 1 ≤ finrank (Spec.map φ) ((Spec.map φ) x)

Tactic:
simp only [IsFinite.SpecMap_iff, Flat.SpecMap_iff] at *

Goal state after:
R S : CommRingCat
x : ↥(Spec S)
φ : R ⟶ S
inst✝¹ : (CommRingCat.Hom.hom φ).Flat
inst✝ : (CommRingCat.Hom.hom φ).Finite
⊢ 1 ≤ finrank (Spec.map φ) ((Spec.map φ) x)
Module: Mathlib.AlgebraicGeometry.Morphisms.FlatRank

Goal state before:
pp: R S : CommRingCat
φ : R ⟶ S
inst✝¹ : Flat (Spec.map φ)
inst✝ : IsFinite (Spec.map φ)
x : ↥(Spec R)
h : 1 x ≤ finrank (Spec.map φ) x
⊢ ∃ a, (Spec.map φ) a = x

Tactic:
simp only [IsFinite.SpecMap_iff, Flat.SpecMap_iff] at *

Goal state after:
R S : CommRingCat
φ : R ⟶ S
x : ↥(Spec R)
h : 1 x ≤ finrank (Spec.map φ) x
inst✝¹ : (CommRingCat.Hom.hom φ).Flat
inst✝ : (CommRingCat.Hom.hom φ).Finite
⊢ ∃ a, (Spec.map φ) a = x
Module: Mathlib.AlgebraicGeometry.Morphisms.FlatRank

Goal state before:
pp: R S : CommRingCat
φ : R ⟶ S
inst✝¹ : Flat (Spec.map φ)
inst✝ : IsFinite (Spec.map φ)
h : finrank (Spec.map φ) = 1
⊢ IsIso (Spec.map φ)

Tactic:
simp only [IsFinite.SpecMap_iff, Flat.SpecMap_iff] at *

Goal state after:
R S : CommRingCat
φ : R ⟶ S
h : finrank (Spec.map φ) = 1
inst✝¹ : (CommRingCat.Hom.hom φ).Flat
inst✝ : (CommRingCat.Hom.hom φ).Finite
⊢ IsIso (Spec.map φ)
Module: Mathlib.RingTheory.KrullDimension.NonZeroDivisors

Goal state before:
pp: case inr
R : Type u_1
inst✝ : CommRing R
σ : Type u_3
a✝ : Nontrivial R
h✝ : Infinite σ
⊢ ringKrullDim (MvPolynomial σ R) = ⊤

Tactic:
rw [ENat.WithBot.eq_top_iff_forall_ge]

Goal state after:
case inr
R : Type u_1
inst✝ : CommRing R
σ : Type u_3
a✝ : Nontrivial R
h✝ : Infinite σ
⊢ ∀ (m : ℕ), ↑m ≤ ringKrullDim (MvPolynomial σ R)
Module: Mathlib.RingTheory.OrderOfVanishing.Basic

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
x : R
⊢ ord R (-x) = ord R x

Tactic:
by
    simp [ord_eq_of_associated (x := -x) (y := x) (by simp)]

Goal state after:
Module: Mathlib.RingTheory.OrderOfVanishing.Noetherian

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
inst✝¹ : IsDomain R
inst✝ : IsDiscreteValuationRing R
x y : R
⊢ min (ord R x) (ord R y) ≤ ord R (x + y)

Tactic:
by
  grw [ord_eq_addVal x, ord_eq_addVal y, ord_eq_addVal (x + y), IsDiscreteValuationRing.addVal_add]

Goal state after:
Module: Mathlib.AlgebraicGeometry.PointsPi

Goal state before:
pp: case hV
ι : Type u
R : ι → CommRingCat
V : Scheme
f : (∐ fun i ↦ Spec (R i)) ⟶ V
g : V ⟶ Spec (CommRingCat.of ((i : ι) → ↑(R i)))
inst✝¹ : IsImmersion g
inst✝ : CompactSpace ↥V
hU' : f ≫ g = sigmaSpec R
⊢ ↑(Scheme.Hom.opensRange (sigmaSpec R)) ⊆ Set.range ⇑g

Tactic:
simpa only [← hU'] using! Set.range_comp_subset_range f g

Goal state after:
Module: Mathlib.AlgebraicGeometry.PointsPi

Goal state before:
pp: ι : Type u
R : ι → CommRingCat
V : Scheme
f : (∐ fun i ↦ Spec (R i)) ⟶ V
inst✝¹ : CompactSpace ↥V
I : Ideal ↑(CommRingCat.of ((i : ι) → ↑(R i)))
e : V ≅ Spec (CommRingCat.of (↑(CommRingCat.of ((i : ι) → ↑(R i))) ⧸ I))
inst✝ : IsImmersion (e.hom ≫ Spec.map (CommRingCat.ofHom (Ideal.Quotient.mk I)))
hU' : f ≫ e.hom ≫ Spec.map (CommRingCat.ofHom (Ideal.Quotient.mk I)) = sigmaSpec R
this✝ : Scheme.Hom.coborderRange (e.hom ≫ Spec.map (CommRingCat.ofHom (Ideal.Quotient.mk I))) = ⊤
this : IsClosedImmersion (e.hom ≫ Spec.map (CommRingCat.ofHom (Ideal.Quotient.mk I)))
⊢ (f ≫ e.hom) ≫ Spec.map (CommRingCat.ofHom (Ideal.Quotient.mk I)) = sigmaSpec R

Tactic:
rwa [Category.assoc]

Goal state after:
Module: Mathlib.AlgebraicGeometry.ProjectiveSpectrum.Topology

Goal state before:
pp: A : Type u_1
σ : Type u_2
inst✝³ : CommRing A
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ℕ → σ
inst✝ : GradedRing 𝒜
f : A
z : ProjectiveSpectrum 𝒜
hz : f ∉ z.asHomogeneousIdeal
i : ℕ
hi : (GradedRing.proj 𝒜 i) f ∉ z.asHomogeneousIdeal
⊢ z ∈ basicOpen 𝒜 ((GradedRing.proj 𝒜 i) f)

Tactic:
by rwa [mem_basicOpen]

Goal state after:
Module: Mathlib.AlgebraicGeometry.ProjectiveSpectrum.StructureSheaf

Goal state before:
pp: A : Type u_1
σ : Type u_2
inst✝³ : CommRing A
inst✝² : SetLike σ A
inst✝¹ : AddSubgroupClass σ A
𝒜 : ℕ → σ
inst✝ : GradedRing 𝒜
⊢ failed to pretty print expression (use 'set_option pp.rawOnError true' for raw representation)

Tactic:
by rintro V U i f ⟨j, r, s, h, w⟩; exact ⟨j, r, s, (h <| i ·), (w <| i ·)⟩

Goal state after:
Module: Mathlib.RingTheory.GradedAlgebra.Radical

Goal state before:
pp: ι : Type u_1
σ : Type u_2
A : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : AddCommMonoid ι
inst✝⁴ : LinearOrder ι
inst✝³ : IsOrderedCancelAddMonoid ι
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ι → σ
inst✝ : GradedRing 𝒜
I : Ideal A
hI : IsHomogeneous 𝒜 I
I_ne_top : I ≠ ⊤
homogeneous_mem_or_mem : ∀ {x y : A}, IsHomogeneousElem 𝒜 x → IsHomogeneousElem 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I
x✝ y : A
hxy : x✝ * y ∈ I
rid₁ : x✝ ∉ I
rid₂ : y ∉ I
set₁ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) x✝) | (proj 𝒜 i) x✝ ∉ I}
set₁_eq : set₁ = {i ∈ DFinsupp.support ((decompose 𝒜) x✝) | (proj 𝒜 i) x✝ ∉ I}
set₂ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
set₂_eq : set₂ = {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
x : A
hx : ∀ a ∈ DFinsupp.support ((decompose 𝒜) x), ↑(((decompose 𝒜) x) a) ∈ I
⊢ x ∈ I

Tactic:
rw [← sum_support_decompose 𝒜 x]

Goal state after:
ι : Type u_1
σ : Type u_2
A : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : AddCommMonoid ι
inst✝⁴ : LinearOrder ι
inst✝³ : IsOrderedCancelAddMonoid ι
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ι → σ
inst✝ : GradedRing 𝒜
I : Ideal A
hI : IsHomogeneous 𝒜 I
I_ne_top : I ≠ ⊤
homogeneous_mem_or_mem : ∀ {x y : A}, IsHomogeneousElem 𝒜 x → IsHomogeneousElem 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I
x✝ y : A
hxy : x✝ * y ∈ I
rid₁ : x✝ ∉ I
rid₂ : y ∉ I
set₁ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) x✝) | (proj 𝒜 i) x✝ ∉ I}
set₁_eq : set₁ = {i ∈ DFinsupp.support ((decompose 𝒜) x✝) | (proj 𝒜 i) x✝ ∉ I}
set₂ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
set₂_eq : set₂ = {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
x : A
hx : ∀ a ∈ DFinsupp.support ((decompose 𝒜) x), ↑(((decompose 𝒜) x) a) ∈ I
⊢ ∑ i ∈ DFinsupp.support ((decompose 𝒜) x), ↑(((decompose 𝒜) x) i) ∈ I
Module: Mathlib.RingTheory.GradedAlgebra.Radical

Goal state before:
pp: ι : Type u_1
σ : Type u_2
A : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : AddCommMonoid ι
inst✝⁴ : LinearOrder ι
inst✝³ : IsOrderedCancelAddMonoid ι
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ι → σ
inst✝ : GradedRing 𝒜
I : Ideal A
hI : IsHomogeneous 𝒜 I
I_ne_top : I ≠ ⊤
homogeneous_mem_or_mem : ∀ {x y : A}, IsHomogeneousElem 𝒜 x → IsHomogeneousElem 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I
x y : A
rid₁ : x ∉ I
rid₂ : y ∉ I
set₁ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₁_eq : set₁ = {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₂ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
set₂_eq : set₂ = {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
nonempty : ∀ x ∉ I, {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}.Nonempty
max₁ : ι := set₁.max' ⋯
max₂ : ι := set₂.max' ⋯
mem_max₁ : max₁ ∈ set₁
mem_max₂ : max₂ ∈ set₂
hxy : (proj 𝒜 (max₁ + max₂)) (x * y) ∈ I
antidiag : Finset (ι × ι) :=
  {z ∈ DFinsupp.support ((decompose 𝒜) x) ×ˢ DFinsupp.support ((decompose 𝒜) y) | z.1 + z.2 = max₁ + max₂}
ha : antidiag = {z ∈ DFinsupp.support ((decompose 𝒜) x) ×ˢ DFinsupp.support ((decompose 𝒜) y) | z.1 + z.2 = max₁ + max₂}
mem_antidiag : (max₁, max₂) ∈ antidiag
eq_add_sum :
  (proj 𝒜 (max₁ + max₂)) (x * y) =
    (proj 𝒜 max₁) x * (proj 𝒜 max₂) y + ∑ ij ∈ antidiag.erase (max₁, max₂), (proj 𝒜 ij.1) x * (proj 𝒜 ij.2) y
⊢ (proj 𝒜 max₁) x * (proj 𝒜 max₂) y ∈ I

Tactic:
rw [eq_sub_of_add_eq eq_add_sum.symm]

Goal state after:
ι : Type u_1
σ : Type u_2
A : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : AddCommMonoid ι
inst✝⁴ : LinearOrder ι
inst✝³ : IsOrderedCancelAddMonoid ι
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ι → σ
inst✝ : GradedRing 𝒜
I : Ideal A
hI : IsHomogeneous 𝒜 I
I_ne_top : I ≠ ⊤
homogeneous_mem_or_mem : ∀ {x y : A}, IsHomogeneousElem 𝒜 x → IsHomogeneousElem 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I
x y : A
rid₁ : x ∉ I
rid₂ : y ∉ I
set₁ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₁_eq : set₁ = {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₂ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
set₂_eq : set₂ = {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
nonempty : ∀ x ∉ I, {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}.Nonempty
max₁ : ι := set₁.max' ⋯
max₂ : ι := set₂.max' ⋯
mem_max₁ : max₁ ∈ set₁
mem_max₂ : max₂ ∈ set₂
hxy : (proj 𝒜 (max₁ + max₂)) (x * y) ∈ I
antidiag : Finset (ι × ι) :=
  {z ∈ DFinsupp.support ((decompose 𝒜) x) ×ˢ DFinsupp.support ((decompose 𝒜) y) | z.1 + z.2 = max₁ + max₂}
ha : antidiag = {z ∈ DFinsupp.support ((decompose 𝒜) x) ×ˢ DFinsupp.support ((decompose 𝒜) y) | z.1 + z.2 = max₁ + max₂}
mem_antidiag : (max₁, max₂) ∈ antidiag
eq_add_sum :
  (proj 𝒜 (max₁ + max₂)) (x * y) =
    (proj 𝒜 max₁) x * (proj 𝒜 max₂) y + ∑ ij ∈ antidiag.erase (max₁, max₂), (proj 𝒜 ij.1) x * (proj 𝒜 ij.2) y
⊢ (proj 𝒜 (max₁ + max₂)) (x * y) - ∑ ij ∈ antidiag.erase (max₁, max₂), (proj 𝒜 ij.1) x * (proj 𝒜 ij.2) y ∈ I
Module: Mathlib.RingTheory.GradedAlgebra.Radical

Goal state before:
pp: case inr
ι : Type u_1
σ : Type u_2
A : Type u_3
inst✝⁶ : CommRing A
inst✝⁵ : AddCommMonoid ι
inst✝⁴ : LinearOrder ι
inst✝³ : IsOrderedCancelAddMonoid ι
inst✝² : SetLike σ A
inst✝¹ : AddSubmonoidClass σ A
𝒜 : ι → σ
inst✝ : GradedRing 𝒜
I : Ideal A
hI : IsHomogeneous 𝒜 I
I_ne_top : I ≠ ⊤
homogeneous_mem_or_mem : ∀ {x y : A}, IsHomogeneousElem 𝒜 x → IsHomogeneousElem 𝒜 y → x * y ∈ I → x ∈ I ∨ y ∈ I
x y : A
rid₁ : x ∉ I
rid₂ : y ∉ I
set₁ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₁_eq : set₁ = {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}
set₂ : Finset ι := {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
set₂_eq : set₂ = {i ∈ DFinsupp.support ((decompose 𝒜) y) | (proj 𝒜 i) y ∉ I}
nonempty : ∀ x ∉ I, {i ∈ DFinsupp.support ((decompose 𝒜) x) | (proj 𝒜 i) x ∉ I}.Nonempty
max₁ : ι := set₁.max' ⋯
max₂ : ι := set₂.max' ⋯
mem_max₁ : max₁ ∈ set₁
mem_max₂ : max₂ ∈ set₂
hxy : (proj 𝒜 (max₁ + max₂)) (x * y) ∈ I
mem_I : (proj 𝒜 max₁) x * (proj 𝒜 max₂) y ∈ I
neither_mem : (proj 𝒜 max₁) x ∉ I ∧ (proj 𝒜 max₂) y ∉ I
_rid : (proj 𝒜 max₁) x * (proj 𝒜 max₂) y ∈ I
h : ↑(((DFinsupp.evalAddMonoidHom max₂).comp (decomposeRingEquiv 𝒜).toRingHom.toAddMonoidHom) y) ∈ I
⊢ False

Tactic:
· apply neither_mem.2 h

Goal state after: