mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.CategoryTheory.Sites.JointlySurjective

Goal state before:
pp: case refine_2
C : Type u_1
inst✝ : Category.{v_1, u_1} C
F : C ⥤ Type u
X : C
R : Presieve X
h : ∀ (x : F.obj X), ∃ Y f, R f ∧ x ∈ Set.range ⇑(ConcreteCategory.hom (F.map f))
x : F.obj X
⊢ ∃ Y g, map F R g ∧ x ∈ Set.range ⇑(ConcreteCategory.hom g)

Tactic:
· obtain ⟨Y, g, hg, hi⟩ := h x
    exact ⟨_, _, ⟨hg⟩, hi⟩

Goal state after:
Module: Mathlib.Geometry.RingedSpace.OpenImmersion

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
X Y Z : PresheafedSpace C
f : X ⟶ Z
hf : IsOpenImmersion f
g : Y ⟶ Z
H : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
l : Y ⟶ X
hl : l ≫ f = g
⊢ l ≫ f = lift f g H ≫ f

Tactic:
hl,

Goal state after:
C : Type u
inst✝ : Category.{v, u} C
X Y Z : PresheafedSpace C
f : X ⟶ Z
hf : IsOpenImmersion f
g : Y ⟶ Z
H : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
l : Y ⟶ X
hl : l ≫ f = g
⊢ g = lift f g H ≫ f
Module: Mathlib.Geometry.RingedSpace.OpenImmersion

Goal state before:
pp: X Y Z : LocallyRingedSpace
f : X ⟶ Z
g : Y ⟶ Z
H : IsOpenImmersion f
H' : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
l : Y ⟶ X
hl : l ≫ f = g
⊢ l ≫ f = lift f g H' ≫ f

Tactic:
hl,

Goal state after:
X Y Z : LocallyRingedSpace
f : X ⟶ Z
g : Y ⟶ Z
H : IsOpenImmersion f
H' : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
l : Y ⟶ X
hl : l ≫ f = g
⊢ g = lift f g H' ≫ f
Module: Mathlib.Geometry.RingedSpace.OpenImmersion

Goal state before:
pp: X Y Z : LocallyRingedSpace
f : X ⟶ Z
g : Y ⟶ Z
H : IsOpenImmersion f
H' : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
this✝ : IsIso (pullback.snd f g)
this :
  (PreservesPullback.iso (forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat) f g).hom ≫
      pullback.fst ((forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat).map f)
        ((forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat).map g) =
    (pullback.fst f g).base
⊢ Function.Surjective
    ⇑(ConcreteCategory.hom
        ((inv (pullback.snd f g)).base ≫
          (PreservesPullback.iso (forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat) f g).hom))

Tactic:
← TopCat.epi_iff_surjective,

Goal state after:
X Y Z : LocallyRingedSpace
f : X ⟶ Z
g : Y ⟶ Z
H : IsOpenImmersion f
H' : Set.range ⇑(ConcreteCategory.hom g.base) ⊆ Set.range ⇑(ConcreteCategory.hom f.base)
this✝ : IsIso (pullback.snd f g)
this :
  (PreservesPullback.iso (forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat) f g).hom ≫
      pullback.fst ((forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat).map f)
        ((forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat).map g) =
    (pullback.fst f g).base
⊢ Epi
    ((inv (pullback.snd f g)).base ≫
      (PreservesPullback.iso (forgetToSheafedSpace ⋙ SheafedSpace.forget CommRingCat) f g).hom)
Module: Mathlib.AlgebraicGeometry.StructureSheaf

Goal state before:
pp: case h.h
R M : Type u
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
f : R
a : M
b : ↥(Submonoid.powers f)
c : M
d : ↥(Submonoid.powers f)
h_eq : const a (↑b) (basicOpen f) ⋯ = const c (↑d) (basicOpen f) ⋯
⊢ f ∈ (⊥.colon {d • a - b • c}).radical

Tactic:
rw [← PrimeSpectrum.vanishingIdeal_zeroLocus_eq_radical, PrimeSpectrum.mem_vanishingIdeal]

Goal state after:
case h.h
R M : Type u
inst✝² : CommRing R
inst✝¹ : AddCommGroup M
inst✝ : Module R M
f : R
a : M
b : ↥(Submonoid.powers f)
c : M
d : ↥(Submonoid.powers f)
h_eq : const a (↑b) (basicOpen f) ⋯ = const c (↑d) (basicOpen f) ⋯
⊢ ∀ x ∈ PrimeSpectrum.zeroLocus ↑(⊥.colon {d • a - b • c}), f ∈ x.asIdeal
Module: Mathlib.AlgebraicGeometry.AffineScheme

Goal state before:
pp: X : Scheme
U : X.Opens
hU : IsAffineOpen U
f : ↑Γ(X, U)
⊢ hU.fromSpec ⁻¹ᵁ X.basicOpen f = (Spec Γ(X, U)).basicOpen ((ConcreteCategory.hom (Scheme.ΓSpecIso Γ(X, U)).inv) f)

Tactic:
rw [Scheme.preimage_basicOpen, hU.fromSpec_app_self]

Goal state after:
X : Scheme
U : X.Opens
hU : IsAffineOpen U
f : ↑Γ(X, U)
⊢ (Spec Γ(X, U)).basicOpen
      ((ConcreteCategory.hom ((Scheme.ΓSpecIso Γ(X, U)).inv ≫ (Spec Γ(X, U)).presheaf.map (eqToHom ⋯).op)) f) =
    (Spec Γ(X, U)).basicOpen ((ConcreteCategory.hom (Scheme.ΓSpecIso Γ(X, U)).inv) f)
Module: Mathlib.CategoryTheory.GlueData

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v, u₁} C
D : GlueData C
i j k : D.J
⊢ inv (D.t' i j k) =
    (pullbackSymmetry (D.f j k) (D.f j i)).hom ≫ D.t' j i k ≫ (pullbackSymmetry (D.f i k) (D.f i j)).hom

Tactic:
· rw [← cancel_mono (pullback.fst (D.f i j) (D.f i k))]
    simp [t_fac, t_fac_assoc]

Goal state after:
Module: Mathlib.Topology.Gluing

Goal state before:
pp: case right.left
α : Type u
inst✝ : TopologicalSpace α
J : Type u
U : J → Opens α
s : Set ↑(ofOpenSubsets U).glued
hs : ∀ (i : (ofOpenSubsets U).J), IsOpen (⇑(ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⁻¹' s)
i : (ofOpenSubsets U).J
x : ↑(of α)
hx' : x ∈ U i
hx : (ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⟨x, hx'⟩ ∈ s
⊢ IsOpen[inst✝]
    (⇑(ConcreteCategory.hom (fromOpenSubsetsGlue U)) '' s ∩ Set.range ⇑(ConcreteCategory.hom (U i).inclusion'))

pp: case right.right
α : Type u
inst✝ : TopologicalSpace α
J : Type u
U : J → Opens α
s : Set ↑(ofOpenSubsets U).glued
hs : ∀ (i : (ofOpenSubsets U).J), IsOpen (⇑(ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⁻¹' s)
i : (ofOpenSubsets U).J
x : ↑(of α)
hx' : x ∈ U i
hx : (ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⟨x, hx'⟩ ∈ s
⊢ (ConcreteCategory.hom (fromOpenSubsetsGlue U)) ((ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⟨x, hx'⟩) ∈
    ⇑(ConcreteCategory.hom (fromOpenSubsetsGlue U)) '' s ∩ Set.range ⇑(ConcreteCategory.hom (U i).inclusion')

Tactic:
· rw [← Set.image_preimage_eq_inter_range]
    apply (Opens.isOpenEmbedding (X := TopCat.of α) (U i)).isOpenMap
    convert! hs i using 1
    rw [← ι_fromOpenSubsetsGlue, coe_comp, Set.preimage_comp]
    congr! 1
    exact Set.preimage_image_eq _ (fromOpenSubsetsGlue_injective U)

Goal state after:
case right.right
α : Type u
inst✝ : TopologicalSpace α
J : Type u
U : J → Opens α
s : Set ↑(ofOpenSubsets U).glued
hs : ∀ (i : (ofOpenSubsets U).J), IsOpen (⇑(ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⁻¹' s)
i : (ofOpenSubsets U).J
x : ↑(of α)
hx' : x ∈ U i
hx : (ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⟨x, hx'⟩ ∈ s
⊢ (ConcreteCategory.hom (fromOpenSubsetsGlue U)) ((ConcreteCategory.hom ((ofOpenSubsets U).ι i)) ⟨x, hx'⟩) ∈
    ⇑(ConcreteCategory.hom (fromOpenSubsetsGlue U)) '' s ∩ Set.range ⇑(ConcreteCategory.hom (U i).inclusion')
Module: Mathlib.AlgebraicGeometry.Gluing

Goal state before:
pp: X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ gluedCoverT' 𝒰 x y z ≫
      gluedCoverT' 𝒰 y z x ≫
        gluedCoverT' 𝒰 z x y ≫ pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) =
    pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫
        gluedCoverT' 𝒰 y z x ≫
          gluedCoverT' 𝒰 z x y ≫ pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.fst (𝒰.f x) (𝒰.f y) =
    pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫ pullback.fst (𝒰.f x) (𝒰.f y)

case h₁
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫
        gluedCoverT' 𝒰 y z x ≫
          gluedCoverT' 𝒰 z x y ≫ pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.snd (𝒰.f x) (𝒰.f y) =
    pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫ pullback.snd (𝒰.f x) (𝒰.f y)
Module: Mathlib.AlgebraicGeometry.Gluing

Goal state before:
pp: X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ gluedCoverT' 𝒰 x y z ≫
      gluedCoverT' 𝒰 y z x ≫
        gluedCoverT' 𝒰 z x y ≫ pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) =
    pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫
        gluedCoverT' 𝒰 y z x ≫
          gluedCoverT' 𝒰 z x y ≫ pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.fst (𝒰.f x) (𝒰.f z) =
    pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫ pullback.fst (𝒰.f x) (𝒰.f z)

case h₁
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫
        gluedCoverT' 𝒰 y z x ≫
          gluedCoverT' 𝒰 z x y ≫ pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.snd (𝒰.f x) (𝒰.f z) =
    pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫ pullback.snd (𝒰.f x) (𝒰.f z)
Module: Mathlib.AlgebraicGeometry.Gluing

Goal state before:
pp: X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ gluedCoverT' 𝒰 x y z ≫ gluedCoverT' 𝒰 y z x ≫ gluedCoverT' 𝒰 z x y =
    𝟙 (pullback (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)))

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫ gluedCoverT' 𝒰 y z x ≫ gluedCoverT' 𝒰 z x y) ≫
      pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) =
    𝟙 (pullback (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))

case h₁
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫ gluedCoverT' 𝒰 y z x ≫ gluedCoverT' 𝒰 z x y) ≫
      pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) =
    𝟙 (pullback (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))) ≫
      pullback.snd (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z))
Module: Mathlib.AlgebraicGeometry.Gluing

Goal state before:
pp: X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ gluedCoverT' 𝒰 x y z ≫ pullback.snd (pullback.fst (𝒰.f y) (𝒰.f z)) (pullback.fst (𝒰.f y) (𝒰.f x)) =
    pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫ (pullbackSymmetry (𝒰.f x) (𝒰.f y)).hom

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫ pullback.snd (pullback.fst (𝒰.f y) (𝒰.f z)) (pullback.fst (𝒰.f y) (𝒰.f x))) ≫
      pullback.fst (𝒰.f y) (𝒰.f x) =
    (pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫
        (pullbackSymmetry (𝒰.f x) (𝒰.f y)).hom) ≫
      pullback.fst (𝒰.f y) (𝒰.f x)

case h₁
X : Scheme
𝒰 : X.OpenCover
x y z : 𝒰.I₀
⊢ (gluedCoverT' 𝒰 x y z ≫ pullback.snd (pullback.fst (𝒰.f y) (𝒰.f z)) (pullback.fst (𝒰.f y) (𝒰.f x))) ≫
      pullback.snd (𝒰.f y) (𝒰.f x) =
    (pullback.fst (pullback.fst (𝒰.f x) (𝒰.f y)) (pullback.fst (𝒰.f x) (𝒰.f z)) ≫
        (pullbackSymmetry (𝒰.f x) (𝒰.f y)).hom) ≫
      pullback.snd (𝒰.f y) (𝒰.f x)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ t 𝒰 f g i i = 𝟙 (v 𝒰 f g i i)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ t 𝒰 f g i i ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i) =
    𝟙 (v 𝒰 f g i i) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i)

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ t 𝒰 f g i i ≫ pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i) =
    𝟙 (v 𝒰 f g i i) ≫ pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ t 𝒰 f g i i ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i) =
    pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ (t 𝒰 f g i i ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i)) ≫ pullback.fst (𝒰.f i ≫ f) g =
    pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i) ≫ pullback.fst (𝒰.f i ≫ f) g

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i : 𝒰.I₀
⊢ (t 𝒰 f g i i ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i)) ≫ pullback.snd (𝒰.f i ≫ f) g =
    pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f i) ≫ pullback.snd (𝒰.f i ≫ f) g
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j = 𝟙 (pullback (fV 𝒰 f g i j) (fV 𝒰 f g i k))

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) =
    𝟙 (pullback (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) =
    𝟙 (pullback (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) =
    pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j) =
    pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j) =
    pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j) =
    pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀.h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
        pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)) ≫
      pullback.fst (𝒰.f i ≫ f) g =
    (pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)) ≫
      pullback.fst (𝒰.f i ≫ f) g

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
        pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)) ≫
      pullback.snd (𝒰.f i ≫ f) g =
    (pullback.fst (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j)) ≫
      pullback.snd (𝒰.f i ≫ f) g
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) =
    pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₁.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k) =
    pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k) =
    pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.snd (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₁.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
      pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k) =
    pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₁.h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
        pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
      pullback.fst (𝒰.f i ≫ f) g =
    (pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
      pullback.fst (𝒰.f i ≫ f) g

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (((t' 𝒰 f g i j k ≫ t' 𝒰 f g j k i ≫ t' 𝒰 f g k i j) ≫ pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k)) ≫
        pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
      pullback.snd (𝒰.f i ≫ f) g =
    (pullback.snd (fV 𝒰 f g i j) (fV 𝒰 f g i k) ≫ pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
      pullback.snd (𝒰.f i ≫ f) g
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ t' 𝒰 f g i j k ≫
      pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
        (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)) =
    pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
        (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
      t 𝒰 f g i j

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫
        pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
          (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i))) ≫
      pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i) =
    (pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
          (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
        t 𝒰 f g i j) ≫
      pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫
        pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
          (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i))) ≫
      pullback.snd (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i) =
    (pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
          (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
        t 𝒰 f g i j) ≫
      pullback.snd (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)
Module: Mathlib.AlgebraicGeometry.Pullbacks

Goal state before:
pp: case h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ (t' 𝒰 f g i j k ≫
        pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
          (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i))) ≫
      pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i) =
    (pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
          (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
        t 𝒰 f g i j) ≫
      pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)

Tactic:
apply pullback.hom_ext

Goal state after:
case h₀.h₀
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫
          pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
            (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i))) ≫
        pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)) ≫
      pullback.fst (𝒰.f j ≫ f) g =
    ((pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
            (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
          t 𝒰 f g i j) ≫
        pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)) ≫
      pullback.fst (𝒰.f j ≫ f) g

case h₁
X Y Z : Scheme
𝒰 : X.OpenCover
f : X ⟶ Z
g : Y ⟶ Z
inst✝ : ∀ (i : 𝒰.I₀), HasPullback (𝒰.f i ≫ f) g
i j k : 𝒰.I₀
⊢ ((t' 𝒰 f g i j k ≫
          pullback.snd (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f k))
            (pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i))) ≫
        pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)) ≫
      pullback.snd (𝒰.f j ≫ f) g =
    ((pullback.fst (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f j))
            (pullback.fst (pullback.fst (𝒰.f i ≫ f) g ≫ 𝒰.f i) (𝒰.f k)) ≫
          t 𝒰 f g i j) ≫
        pullback.fst (pullback.fst (𝒰.f j ≫ f) g ≫ 𝒰.f j) (𝒰.f i)) ≫
      pullback.snd (𝒰.f j ≫ f) g