mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.Sets.CompactOpenCovered

Goal state before:
pp: S : Type u_1
ι : Type u_2
X : ι → Type u_3
f : (i : ι) → X i → S
inst✝³ : (i : ι) → TopologicalSpace (X i)
inst✝² : ∀ (i : ι), PrespectralSpace (X i)
inst✝¹ : TopologicalSpace S
σ : Type u_4
Y : σ → Type u_5
inst✝ : (i : σ) → TopologicalSpace (Y i)
g : (i : σ) → Y i → S
a : σ → ι
t : (i : σ) → Y i → X (a i)
ht : ∀ (i : σ), Continuous (t i)
hge : ∀ (i : σ), g i = f (a i) ∘ t i
hf✝ : ∀ (i : ι), Continuous (f i)
U : Set S
ho✝ : IsOpen U
p : (i : σ) × Y i → (i : ι) × X i := Sigma.map a t
hcomp : (fun x ↦ f x.fst x.snd) ∘ p = fun x ↦ g x.fst x.snd
hp : Continuous p
hf : Continuous fun p ↦ f p.fst p.snd
V : Opens ((i : σ) × Y i)
hV : IsCompact V.carrier
heq : (fun p ↦ g p.fst p.snd) '' V.carrier = U
K : Set ((i : ι) × X i)
hK : IsCompact K
ho : IsOpen K
hVK : p '' V.carrier ⊆ K
hKU : K ⊆ (fun p ↦ f p.fst p.snd) ⁻¹' U
⊢ (fun x ↦ f x.fst x.snd) '' K ⊆ (fun p ↦ f p.fst p.snd) '' { carrier := K, is_open' := ho }.carrier

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.ColimitsOver

Goal state before:
pp: P : MorphismProperty Scheme
inst✝⁵ : P.IsStableUnderBaseChange
inst✝⁴ : P.IsMultiplicative
S : Scheme
J : Type u_1
inst✝³ : Category.{v_1, u_1} J
D : J ⥤ P.Over ⊤ S
𝒰 : S.OpenCover
inst✝² : Category.{v_2, u_2} 𝒰.I₀
inst✝¹ : LocallyDirected 𝒰
d : ColimitGluingData D 𝒰
inst✝ :
  ∀ {i j : 𝒰.I₀} (hij : i ⟶ j), PreservesColimitsOfShape J (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij))
i j : 𝒰.I₀
hij : i ⟶ j
iso1 : (d.cocone i).pt ≅ ((MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij)).mapCocone (d.cocone j)).pt :=
  (d.isColimit i).coconePointsIsoOfNatIso
    (isColimitOfPreserves (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij)) (d.isColimit j))
    (D.isoWhiskerLeft (MorphismProperty.Over.pullbackComp (Cover.trans 𝒰 hij) (𝒰.f j) (𝒰.f i) ⋯) ≪≫
      (D.associator (MorphismProperty.Over.pullback P ⊤ (𝒰.f j))
          (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij))).symm)
heq :
  (MorphismProperty.Over.map ⊤ ⋯).map iso1.hom ≫
      (MorphismProperty.Over.mapPullbackAdj P ⊤ (Cover.trans 𝒰 hij) ⋯ trivial).counit.app (d.cocone j).pt =
    d.transitionMap hij
iso2 : (d.cocone i).pt.left ≅ pullback (d.cocone j).pt.hom (Cover.trans 𝒰 hij) :=
  (MorphismProperty.Over.forget P ⊤ (𝒰.X i) ⋙ CategoryTheory.Over.forget (𝒰.X i)).mapIso iso1
⊢ (d.cocone j).pt.hom ≫ (Iso.refl ((Functor.fromPUnit (𝒰.X j)).obj (d.cocone j).pt.right)).hom =
    (Iso.refl ((𝟭 Scheme).obj (d.cocone j).pt.left)).hom ≫ (d.cocone j).pt.hom

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.ColimitsOver

Goal state before:
pp: P : MorphismProperty Scheme
inst✝⁵ : P.IsStableUnderBaseChange
inst✝⁴ : P.IsMultiplicative
S : Scheme
J : Type u_1
inst✝³ : Category.{v_1, u_1} J
D : J ⥤ P.Over ⊤ S
𝒰 : S.OpenCover
inst✝² : Category.{v_2, u_2} 𝒰.I₀
inst✝¹ : LocallyDirected 𝒰
d : ColimitGluingData D 𝒰
inst✝ :
  ∀ {i j : 𝒰.I₀} (hij : i ⟶ j), PreservesColimitsOfShape J (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij))
i j : 𝒰.I₀
hij : i ⟶ j
iso1 : (d.cocone i).pt ≅ ((MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij)).mapCocone (d.cocone j)).pt :=
  (d.isColimit i).coconePointsIsoOfNatIso
    (isColimitOfPreserves (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij)) (d.isColimit j))
    (D.isoWhiskerLeft (MorphismProperty.Over.pullbackComp (Cover.trans 𝒰 hij) (𝒰.f j) (𝒰.f i) ⋯) ≪≫
      (D.associator (MorphismProperty.Over.pullback P ⊤ (𝒰.f j))
          (MorphismProperty.Over.pullback P ⊤ (Cover.trans 𝒰 hij))).symm)
heq :
  (MorphismProperty.Over.map ⊤ ⋯).map iso1.hom ≫
      (MorphismProperty.Over.mapPullbackAdj P ⊤ (Cover.trans 𝒰 hij) ⋯ trivial).counit.app (d.cocone j).pt =
    d.transitionMap hij
iso2 : (d.cocone i).pt.left ≅ pullback (d.cocone j).pt.hom (Cover.trans 𝒰 hij) :=
  (MorphismProperty.Over.forget P ⊤ (𝒰.X i) ⋙ CategoryTheory.Over.forget (𝒰.X i)).mapIso iso1
⊢ Cover.trans 𝒰 hij ≫ (Iso.refl ((Functor.fromPUnit (𝒰.X j)).obj (d.cocone j).pt.right)).hom =
    (Iso.refl (𝒰.X i)).hom ≫ Cover.trans 𝒰 hij

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.Cover.QuasiCompact

Goal state before:
pp: S : Scheme
𝒰✝ 𝒰 : PreZeroHypercover S
K : Precoverage Scheme
inst✝ : QuasiCompactCover 𝒰
T : Scheme
f : T ⟶ S
U' : T.Opens
hU' : IsAffineOpen U'
U : S.Opens
hU : IsAffineOpen U
hsub : ⇑f '' ↑U' ⊆ ↑U
s : Set 𝒰.I₀
hf : s.Finite
V : (i : 𝒰.I₀) → i ∈ s → TopologicalSpace.Opens ((fun x ↦ ↥(𝒰.X x)) i)
hc : ∀ (i : 𝒰.I₀) (h : i ∈ s), IsCompact (V i h).carrier
heq : ⋃ i, ⋃ (h : i ∈ s), (fun x ↦ ⇑(𝒰.f x)) i '' ↑(V i h) = ↑U
⊢ ⋃ i,
      ⋃ (h : i ∈ s),
        (fun x ↦ ⇑((PreZeroHypercover.pullback₁ f 𝒰).f x)) i ''
          ↑((fun i hi ↦ pullback.fst f (𝒰.f i) ⁻¹ᵁ U' ⊓ pullback.snd f (𝒰.f i) ⁻¹ᵁ V i hi) i h) ⊆
    ↑U'

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.Cover.Sigma

Goal state before:
pp: P : MorphismProperty Scheme
S : Scheme
inst✝² : IsZariskiLocalAtSource P
inst✝¹ : UnivLE.{v, u}
inst✝ : P.IsMultiplicative
𝒰 𝒱 : Cover (precoverage P) S
f : 𝒰 ⟶ 𝒱
x✝ : 𝒰.sigma.I₀
⊢ ∀ (b : 𝒰.I₀),
    Sigma.ι 𝒰.X b ≫ (Sigma.desc fun j ↦ f.h₀ j ≫ Sigma.ι 𝒱.X (f.s₀ j)) ≫ 𝒱.sigma.f default =
      Sigma.ι 𝒰.X b ≫ 𝒰.sigma.f x✝

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.Cover.Sigma

Goal state before:
pp: P : MorphismProperty Scheme
S : Scheme
inst✝² : IsZariskiLocalAtSource P
inst✝¹ : UnivLE.{v, u}
inst✝ : P.IsMultiplicative
𝒰✝ 𝒱 𝒰 : Cover (precoverage P) S
j : 𝒰.sigma.I₀
⊢ ∀ (b : 𝒰.I₀), Sigma.ι 𝒰.X b ≫ (Hom.sigma (𝟙 𝒰)).h₀ j = Sigma.ι 𝒰.X b ≫ (𝟙 𝒰.sigma).h₀ j

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.Cover.Sigma

Goal state before:
pp: P : MorphismProperty Scheme
S : Scheme
inst✝² : IsZariskiLocalAtSource P
inst✝¹ : UnivLE.{v, u}
inst✝ : P.IsMultiplicative
𝒰 𝒱 X✝ Y✝ Z✝ : Cover (precoverage P) S
f : X✝ ⟶ Y✝
g : Y✝ ⟶ Z✝
j : X✝.sigma.I₀
⊢ ∀ (b : X✝.I₀), Sigma.ι X✝.X b ≫ (Hom.sigma (f ≫ g)).h₀ j = Sigma.ι X✝.X b ≫ (Hom.sigma f ≫ Hom.sigma g).h₀ j

Tactic:
by simp

Goal state after:
Module: Mathlib.CategoryTheory.EffectiveEpi.Comp

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v_1, u_1} C
B B' : C
α : Type u_2
X : α → C
π : (a : α) → X a ⟶ B
i : B ⟶ B'
inst✝¹ : EffectiveEpiFamily X π
inst✝ : IsIso i
W✝ : C
x✝² : (a : α) → X a ⟶ W✝
x✝¹ : ∀ {Z : C} (a₁ a₂ : α) (g₁ : Z ⟶ X a₁) (g₂ : Z ⟶ X a₂), g₁ ≫ π a₁ ≫ i = g₂ ≫ π a₂ ≫ i → g₁ ≫ x✝² a₁ = g₂ ≫ x✝² a₂
x✝ : α
⊢ (π x✝ ≫ i) ≫ inv i ≫ EffectiveEpiFamily.desc X π x✝² ⋯ = x✝² x✝

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝⁴ : Category.{u, u} I
S X : Scheme
D : I ⥤ Scheme
t : D ⟶ (Functor.const I).obj S
f : X ⟶ S
c : Cone D
hc : IsLimit c
inst✝³ : ∀ (i : I), CompactSpace ↥(D.obj i)
inst✝² : LocallyOfFiniteType f
inst✝¹ : IsCofiltered I
inst✝ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
a b : D.obj i ⟶ X
ha : t.app i = a ≫ f
hb : t.app i = b ≫ f
hab : c.π.app i ≫ a = c.π.app i ≫ b
this : ∀ (i : I), IsAffineHom (c.π.app i)
A : ExistsHomHomCompEqCompAux D t f := ⋯
𝒰 : (pullback.diagonalObj f).OpenCover := ⋯
W : (pullback.diagonalObj f).Opens := ⋯
k : A.𝒰D.I₀ → I
hki' : (j : A.𝒰D.I₀) → k j ⟶ A.i'
heq :
  ∀ (j : A.𝒰D.I₀),
    (Precoverage.ZeroHypercover.pullback₁ (D.map (hki' j)) A.𝒰D).f j ≫ D.map (hki' j ≫ A.hii') ≫ A.a =
      (Precoverage.ZeroHypercover.pullback₁ (D.map (hki' j)) A.𝒰D).f j ≫ D.map (hki' j ≫ A.hii') ≫ A.b
𝒰Df : (D.obj A.i').OpenCover := ⋯
h : Nonempty ↥(D.obj A.i')
O : Finset I := ⋯
o : 𝒰Df.I₀ := ⋯
ho : k (Cover.idx A.𝒰D ↑o) ∈ O
l : I
hl1 : {X : I} → X ∈ O → (l ⟶ X)
hl2 :
  ∀ {X_1 Y : I} (mX : X_1 ∈ O) (mY : Y ∈ O) {f_1 : X_1 ⟶ Y},
    ⟨X_1, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈
        Finset.image (fun i ↦ ⟨k (Cover.idx A.𝒰D ↑i), ⟨A.i', ⟨⋯, ⟨⋯, hki' (Cover.idx A.𝒰D ↑i)⟩⟩⟩⟩) Finset.univ →
      hl1 mX ≫ f_1 = hl1 mY
w v : 𝒰Df.I₀
⊢ hl1 ⋯ ≫ hki' (Cover.idx A.𝒰D ↑w) = hl1 ⋯

Tactic:
exact hl2 _ _ (Finset.mem_image_of_mem _ (Finset.mem_univ _))

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝⁴ : Category.{u, u} I
S X : Scheme
D : I ⥤ Scheme
t : D ⟶ (Functor.const I).obj S
f : X ⟶ S
c : Cone D
hc : IsLimit c
inst✝³ : ∀ (i : I), CompactSpace ↥(D.obj i)
inst✝² : LocallyOfFiniteType f
inst✝¹ : IsCofiltered I
inst✝ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
a b : D.obj i ⟶ X
ha : t.app i = a ≫ f
hb : t.app i = b ≫ f
hab : c.π.app i ≫ a = c.π.app i ≫ b
this : ∀ (i : I), IsAffineHom (c.π.app i)
A : ExistsHomHomCompEqCompAux D t f :=
  { c := c, hc := hc, i := i, a := a, ha := ha, b := b, hb := hb, hab := hab, 𝒰S := S.affineCover, h𝒰S := ⋯,
    𝒰X := fun i ↦ ((Precoverage.ZeroHypercover.pullback₁ f S.affineCover).X i).affineCover, h𝒰X := ⋯ }
𝒰 : (pullback.diagonalObj f).OpenCover := Pullback.diagonalCover f A.𝒰S A.𝒰X
W : (pullback.diagonalObj f).Opens := Pullback.diagonalCoverDiagonalRange f A.𝒰S A.𝒰X
k : A.𝒰D.I₀ → I
hki' : (j : A.𝒰D.I₀) → k j ⟶ A.i'
heq :
  ∀ (j : A.𝒰D.I₀),
    (Precoverage.ZeroHypercover.pullback₁ (D.map (hki' j)) A.𝒰D).f j ≫ D.map (hki' j ≫ A.hii') ≫ A.a =
      (Precoverage.ZeroHypercover.pullback₁ (D.map (hki' j)) A.𝒰D).f j ≫ D.map (hki' j ≫ A.hii') ≫ A.b
𝒰Df : (D.obj A.i').OpenCover := A.𝒰D.finiteSubcover
h : Nonempty ↥(D.obj A.i')
O : Finset I := {A.i'} ∪ Finset.image (fun i ↦ k (Cover.idx A.𝒰D ↑i)) Finset.univ
o : 𝒰Df.I₀ := ⋯.some
ho : k (Cover.idx A.𝒰D ↑o) ∈ O
l : I
hl1 : {X : I} → X ∈ O → (l ⟶ X)
hl2 :
  ∀ {X_1 Y : I} (mX : X_1 ∈ O) (mY : Y ∈ O) {f_1 : X_1 ⟶ Y},
    ⟨X_1, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈
        Finset.image (fun i ↦ ⟨k (Cover.idx A.𝒰D ↑i), ⟨A.i', ⟨⋯, ⟨⋯, hki' (Cover.idx A.𝒰D ↑i)⟩⟩⟩⟩) Finset.univ →
      hl1 mX ≫ f_1 = hl1 mY
w v : 𝒰Df.I₀
⊢ v ∈ Finset.univ

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.EffectiveEpi

Goal state before:
pp: X Y S : Scheme
inst✝³ : IsAffine X
inst✝² : IsAffine Y
π : X ⟶ Y
inst✝¹ : Surjective π
inst✝ : Flat π
f : X ⟶ S
hf : fst π π ≫ f = snd π π ≫ f
b : ↑Y.toPresheafedSpace ⟶ ↑S.toPresheafedSpace
hfac : π.base ≫ b = f.base
𝒰 : Y.OpenCover := Y.openCoverOfIsOpenCover (fun V ↦ (↑V).1) ⋯
i : 𝒰.I₀
⊢ ∃ u, fst π (𝒰.f i) ≫ f = snd π (𝒰.f i) ≫ u

Tactic:
have : IsAffine (𝒰.X i) := i.2.1

Goal state after:
X Y S : Scheme
inst✝³ : IsAffine X
inst✝² : IsAffine Y
π : X ⟶ Y
inst✝¹ : Surjective π
inst✝ : Flat π
f : X ⟶ S
hf : fst π π ≫ f = snd π π ≫ f
b : ↑Y.toPresheafedSpace ⟶ ↑S.toPresheafedSpace
hfac : π.base ≫ b = f.base
𝒰 : Y.OpenCover := Y.openCoverOfIsOpenCover (fun V ↦ (↑V).1) ⋯
i : 𝒰.I₀
this : IsAffine (𝒰.X i)
⊢ ∃ u, fst π (𝒰.f i) ≫ f = snd π (𝒰.f i) ≫ u
Module: Mathlib.AlgebraicGeometry.EllipticCurve.Weierstrass

Goal state before:
pp: R : Type u
inst✝ : CommRing R
W : WeierstrassCurve R
⊢ 4 * W.b₈ = W.b₂ * W.b₆ - W.b₄ ^ 2

Tactic:
by
  simp only [b₂, b₄, b₆, b₈]
  ring1

Goal state after:
Module: Mathlib.RingTheory.Spectrum.Prime.ChevalleyComplexity

Goal state before:
pp: k₀ k : ℕ
D : ℕ → ℕ
⊢ degBound k₀ (fun t ↦ Nat.casesOn t k D) (0 + 1) = (k₀ * k) ^ (k₀ * k) * degBound (k₀ * k) ((k₀ * k) ^ (k₀ * k) • D) 0

Tactic:
by simp

Goal state after:
Module: Mathlib.RingTheory.Spectrum.Prime.ChevalleyComplexity

Goal state before:
pp: k₀ k : ℕ
D : ℕ → ℕ
⊢ numBound k₀ (fun x ↦ Nat.casesOn x k D) (0 + 1) = numBound (k₀ * k) ((k₀ * k) ^ (k₀ * k) • D) 0

Tactic:
by simp

Goal state after:
Module: Mathlib.RingTheory.Spectrum.Prime.ChevalleyComplexity

Goal state before:
pp: k₁ k₂ : ℕ
D₁ D₂ : ℕ → ℕ
hk : k₁ ≤ k₂
hD : ∀ i < 0, D₁ i ≤ D₂ i
⊢ degBound k₁ D₁ 0 ≤ degBound k₂ D₂ 0

Tactic:
by simp

Goal state after:
Module: Mathlib.RingTheory.Spectrum.Prime.ChevalleyComplexity

Goal state before:
pp: k : ℕ
D : ℕ → ℕ
⊢ 0 < degBound k D 0

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
x : ↥t
⊢ i ∈ insert i (Finset.image j t)

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
k : I
fk : {X : I} → X ∈ insert i (Finset.image j t) → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ insert i (Finset.image j t)) (mY : Y ∈ insert i (Finset.image j t)) {f_1 : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈ Finset.image (fun x ↦ ⟨j ↑x, ⟨i, ⟨⋯, ⟨⋯, f ↑x⟩⟩⟩⟩) t.attach → fk mX ≫ f_1 = fk mY
⊢ i ∈ insert i (Finset.image j t)

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
k : I
fk : {X : I} → X ∈ insert i (Finset.image j t) → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ insert i (Finset.image j t)) (mY : Y ∈ insert i (Finset.image j t)) {f_1 : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈ Finset.image (fun x ↦ ⟨j ↑x, ⟨i, ⟨⋯, ⟨⋯, f ↑x⟩⟩⟩⟩) t.attach → fk mX ≫ f_1 = fk mY
x : ↥(D.obj k)
⊢ i ∈ insert i (Finset.image j t)

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
k : I
fk : {X : I} → X ∈ insert i (Finset.image j t) → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ insert i (Finset.image j t)) (mY : Y ∈ insert i (Finset.image j t)) {f_1 : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈ Finset.image (fun x ↦ ⟨j ↑x, ⟨i, ⟨⋯, ⟨⋯, f ↑x⟩⟩⟩⟩) t.attach → fk mX ≫ f_1 = fk mY
x : ↥(D.obj k)
l : ↥(D.obj i)
hl : l ∈ t
hlU : (D.map (fk ⋯)) x ∈ ↑(U l)
⊢ i ∈ insert i (Finset.image j t)

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
k : I
fk : {X : I} → X ∈ insert i (Finset.image j t) → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ insert i (Finset.image j t)) (mY : Y ∈ insert i (Finset.image j t)) {f_1 : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈ Finset.image (fun x ↦ ⟨j ↑x, ⟨i, ⟨⋯, ⟨⋯, f ↑x⟩⟩⟩⟩) t.attach → fk mX ≫ f_1 = fk mY
x : ↥(D.obj k)
l : ↥(D.obj i)
hl : l ∈ t
hlU : (D.map (fk ⋯)) x ∈ ↑(U l)
⊢ ⟨l, hl⟩ ∈ t.attach

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝³ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝² : IsCofiltered I
inst✝¹ : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
i : I
inst✝ : CompactSpace ↥(D.obj i)
s : ↑Γ(D.obj i, ⊤)
hs : (ConcreteCategory.hom (Scheme.Hom.appTop (c.π.app i))) s = 0
U : ↥(D.obj i) → (D.obj i).Opens
hU : ∀ (x : ↥(D.obj i)), IsAffineOpen (U x)
hxU : ∀ (x : ↥(D.obj i)), x ∈ U x
j : ↥(D.obj i) → I
f : (x : ↥(D.obj i)) → j x ⟶ i
H : ∀ (x : ↥(D.obj i)), (ConcreteCategory.hom (Scheme.Hom.app (D.map (f x)) (U x))) ((s |_ U x) ⋯) = 0
t : Finset ↥(D.obj i)
ht : ⋃ x ∈ t, ↑(U x) = ⊤
k : I
fk : {X : I} → X ∈ insert i (Finset.image j t) → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ insert i (Finset.image j t)) (mY : Y ∈ insert i (Finset.image j t)) {f_1 : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f_1⟩⟩⟩⟩ ∈ Finset.image (fun x ↦ ⟨j ↑x, ⟨i, ⟨⋯, ⟨⋯, f ↑x⟩⟩⟩⟩) t.attach → fk mX ≫ f_1 = fk mY
x : ↥(D.obj k)
l : ↥(D.obj i)
hl : l ∈ t
hlU : (D.map (fk ⋯)) x ∈ ↑(U l)
⊢ ⟨j ↑⟨l, hl⟩, ⟨i, ⟨⋯, ⟨⋯, f ↑⟨l, hl⟩⟩⟩⟩⟩ = ⟨j l, ⟨i, ⟨⋯, ⟨⋯, f l⟩⟩⟩⟩

Tactic:
by simp

Goal state after:
Module: Mathlib.AlgebraicGeometry.EllipticCurve.Affine.Formula

Goal state before:
pp: R : Type r
inst✝ : CommRing R
W' : Affine R
x y : R
⊢ W'.Equation x y ∧ (W'.a₁ * W'.negY x y ≠ 3 * x ^ 2 + 2 * W'.a₂ * x + W'.a₄ ∨ W'.negY x y ≠ W'.negY x (W'.negY x y)) ↔
    W'.Nonsingular x y

Tactic:
negY_negY,

Goal state after:
R : Type r
inst✝ : CommRing R
W' : Affine R
x y : R
⊢ W'.Equation x y ∧ (W'.a₁ * W'.negY x y ≠ 3 * x ^ 2 + 2 * W'.a₂ * x + W'.a₄ ∨ W'.negY x y ≠ y) ↔ W'.Nonsingular x y
Module: Mathlib.AlgebraicGeometry.EllipticCurve.Affine.Formula

Goal state before:
pp: case pos
F : Type u
inst✝¹ : Field F
W : Affine F
inst✝ : DecidableEq F
x₁ y₁ : F
h₁ h₂ : y₁ ^ 2 + W.a₁ * x₁ * y₁ + W.a₃ * y₁ = x₁ ^ 3 + W.a₂ * x₁ ^ 2 + W.a₄ * x₁ + W.a₆
hxy : ¬(x₁ = x₁ ∧ y₁ = W.negY x₁ y₁)
hy : y₁ - (-y₁ - W.a₁ * x₁ - W.a₃) ≠ 0
⊢ { a := 1,
      b :=
        -((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 -
            W.a₁ * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          W.a₂,
      c :=
        2 * x₁ * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 +
            (W.a₁ * x₁ - 2 * y₁ - W.a₃) * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          (-W.a₁ * y₁ + W.a₄),
      d :=
        -x₁ ^ 2 * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 +
            (2 * x₁ * y₁ + W.a₃ * x₁) * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) -
          (y₁ ^ 2 + W.a₃ * y₁ - W.a₆) } =
    { a := 1, b := -(x₁ + x₁ + W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁))),
      c :=
        x₁ * x₁ + x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)),
      d := -(x₁ * x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁))) }

Tactic:
replace hy : y₁ - (-y₁ - x₁ * W.a₁ - W.a₃) ≠ 0 := by convert! hy using 1; ring

Goal state after:
case pos
F : Type u
inst✝¹ : Field F
W : Affine F
inst✝ : DecidableEq F
x₁ y₁ : F
h₁ h₂ : y₁ ^ 2 + W.a₁ * x₁ * y₁ + W.a₃ * y₁ = x₁ ^ 3 + W.a₂ * x₁ ^ 2 + W.a₄ * x₁ + W.a₆
hxy : ¬(x₁ = x₁ ∧ y₁ = W.negY x₁ y₁)
hy : y₁ - (-y₁ - x₁ * W.a₁ - W.a₃) ≠ 0
⊢ { a := 1,
      b :=
        -((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 -
            W.a₁ * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          W.a₂,
      c :=
        2 * x₁ * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 +
            (W.a₁ * x₁ - 2 * y₁ - W.a₃) * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          (-W.a₁ * y₁ + W.a₄),
      d :=
        -x₁ ^ 2 * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) ^ 2 +
            (2 * x₁ * y₁ + W.a₃ * x₁) * ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) -
          (y₁ ^ 2 + W.a₃ * y₁ - W.a₆) } =
    { a := 1, b := -(x₁ + x₁ + W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁))),
      c :=
        x₁ * x₁ + x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)) +
          x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁)),
      d := -(x₁ * x₁ * W.addX x₁ x₁ ((3 * x₁ ^ 2 + 2 * W.a₂ * x₁ + W.a₄ - W.a₁ * y₁) / (y₁ - W.negY x₁ y₁))) }
Module: Mathlib.AlgebraicGeometry.AffineTransitionLimit

Goal state before:
pp: I : Type u
inst✝⁴ : Category.{u, u} I
D : I ⥤ Scheme
c : Cone D
hc : IsLimit c
inst✝³ : IsCofiltered I
inst✝² : ∀ {i j : I} (f : i ⟶ j), IsAffineHom (D.map f)
s : ↑Γ(c.pt, ⊤)
inst✝¹ : ∀ (i : I), CompactSpace ↥(D.obj i)
inst✝ : ∀ (i : I), QuasiSeparatedSpace ↥(D.obj i)
this : CompactSpace ↥c.pt
i : ↥c.pt → I
U : (x : ↥c.pt) → (D.obj (i x)).Opens
hU : ∀ (x : ↥c.pt), IsAffineOpen (U x)
hxU : ∀ (x : ↥c.pt), (c.π.app (i x)) x ∈ U x
t : (x : ↥c.pt) → ↑Γ(D.obj (i x), U x)
ht : ∀ (x : ↥c.pt), (ConcreteCategory.hom (Scheme.Hom.app (c.π.app (i x)) (U x))) (t x) = (s |_ c.π.app (i x) ⁻¹ᵁ U x) ⋯
j : ↥c.pt → ↥c.pt → I
fjx : (x y : ↥c.pt) → j x y ⟶ i x
fjy : (x y : ↥c.pt) → j x y ⟶ i y
hj :
  ∀ (x y : ↥c.pt),
    ((ConcreteCategory.hom (Scheme.Hom.app (D.map (fjx x y)) (U x))) (t x) |_
          (D.map (fjx x y) ⁻¹ᵁ U x ⊓ D.map (fjy x y) ⁻¹ᵁ U y))
        ⋯ =
      ((ConcreteCategory.hom (Scheme.Hom.app (D.map (fjy x y)) (U y))) (t y) |_
          (D.map (fjx x y) ⁻¹ᵁ U x ⊓ D.map (fjy x y) ⁻¹ᵁ U y))
        ⋯
σ : Finset ↥c.pt
hσ : ⋃ x ∈ σ, (c.π.app (i x) ⁻¹ᵁ U x).carrier = ⊤
σi : ↥c.pt → ↥c.pt
hσiσ : ∀ (x : ↥c.pt), σi x ∈ σ
hσi : ∀ (x : ↥c.pt), x ∈ (c.π.app (i (σi x)) ⁻¹ᵁ U (σi x)).carrier
S : Finset I := Finset.image i σ ∪ Finset.image₂ j σ σ
hiS : ∀ {x : ↥c.pt}, x ∈ σ → i x ∈ S
hjS : ∀ {x y : ↥c.pt}, x ∈ σ → y ∈ σ → j x y ∈ S
k : I
fk : {X : I} → X ∈ S → (k ⟶ X)
hk :
  ∀ {X Y : I} (mX : X ∈ S) (mY : Y ∈ S) {f : X ⟶ Y},
    ⟨X, ⟨Y, ⟨mX, ⟨mY, f⟩⟩⟩⟩ ∈
        Finset.image₂ (fun x y ↦ ⟨j ↑x ↑y, ⟨i ↑x, ⟨⋯, ⟨⋯, fjx ↑x ↑y⟩⟩⟩⟩) σ.attach σ.attach ∪
          Finset.image₂ (fun x y ↦ ⟨j ↑x ↑y, ⟨i ↑y, ⟨⋯, ⟨⋯, fjy ↑x ↑y⟩⟩⟩⟩) σ.attach σ.attach →
      fk mX ≫ f = fk mY
x y : ↥c.pt
hx : x ∈ σ
hy : y ∈ σ
⊢ ⟨x, hx⟩ ∈ σ.attach

Tactic:
by simp

Goal state after: