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

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
F✝ : C ⥤ Type w
F : Cᵒᵖ ⥤ Type (max w v)
X✝ Y✝ : CostructuredArrow uliftYoneda.{w, v, u} F
f : X✝ ⟶ Y✝
⊢ (ConcreteCategory.hom (F.map f.left.op)) (uliftYonedaEquiv Y✝.hom) = uliftYonedaEquiv X✝.hom

Tactic:
rw [← CostructuredArrow.w f, uliftYonedaEquiv_naturality, Quiver.Hom.unop_op]

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Shapes.Grothendieck

Goal state before:
pp: C : Type u₁
inst✝² : Category.{v₁, u₁} C
F : C ⥤ Cat
H : Type u₂
inst✝¹ : Category.{v₂, u₂} H
G : Grothendieck F ⥤ H
inst✝ : ∀ {X Y : C} (f : X ⟶ Y), HasColimit ((F.map f).toFunctor ⋙ Grothendieck.ι F Y ⋙ G)
x✝¹ x✝ : Grothendieck F
f : x✝¹ ⟶ x✝
⊢ G.map f ≫ colimit.ι (Grothendieck.ι F x✝.base ⋙ G) x✝.fiber =
    G.map ((Grothendieck.ιNatTrans f.base).app x✝¹.fiber) ≫
      colimit.ι (Grothendieck.ι F x✝.base ⋙ G) ((F.map f.base).toFunctor.obj x✝¹.fiber)

Tactic:
rw [← colimit.w (Grothendieck.ι F _ ⋙ G) f.fiber]

Goal state after:
C : Type u₁
inst✝² : Category.{v₁, u₁} C
F : C ⥤ Cat
H : Type u₂
inst✝¹ : Category.{v₂, u₂} H
G : Grothendieck F ⥤ H
inst✝ : ∀ {X Y : C} (f : X ⟶ Y), HasColimit ((F.map f).toFunctor ⋙ Grothendieck.ι F Y ⋙ G)
x✝¹ x✝ : Grothendieck F
f : x✝¹ ⟶ x✝
⊢ G.map f ≫ colimit.ι (Grothendieck.ι F x✝.base ⋙ G) x✝.fiber =
    G.map ((Grothendieck.ιNatTrans f.base).app x✝¹.fiber) ≫
      (Grothendieck.ι F x✝.base ⋙ G).map f.fiber ≫ colimit.ι (Grothendieck.ι F x✝.base ⋙ G) x✝.fiber
Module: Mathlib.CategoryTheory.Limits.Shapes.Grothendieck

Goal state before:
pp: C : Type u₁
inst✝² : Category.{v₁, u₁} C
F : C ⥤ Cat
H : Type u₂
inst✝¹ : Category.{v₂, u₂} H
G : Grothendieck F ⥤ H
inst✝ : ∀ {X Y : C} (f : X ⟶ Y), HasColimit ((F.map f).toFunctor ⋙ Grothendieck.ι F Y ⋙ G)
c : Cocone (fiberwiseColimit G)
hc : IsColimit c
s : Cocone G
m : (coconeOfCoconeFiberwiseColimit c).pt ⟶ s.pt
X : C
hm : ∀ (j : Grothendieck F), colimit.ι (Grothendieck.ι F j.base ⋙ G) j.fiber ≫ c.ι.app j.base ≫ m = s.ι.app j
d : ↑(F.obj X)
⊢ colimit.ι (Grothendieck.ι F X ⋙ G) d ≫ c.ι.app X ≫ m =
    colimit.ι (Grothendieck.ι F X ⋙ G) d ≫ colimit.desc (Grothendieck.ι F X ⋙ G) (Cocone.whisker (Grothendieck.ι F X) s)

Tactic:
simp [hm ⟨X, d⟩]

Goal state after:
Module: Mathlib.RingTheory.FinitePresentation

Goal state before:
pp: R : Type w₁
A : Type w₂
B : Type w₃
inst✝⁸ : CommRing R
inst✝⁷ : CommRing A
inst✝⁶ : Algebra R A
inst✝⁵ : CommRing B
inst✝⁴ : Algebra R B
inst✝³ : Algebra A B
inst✝² : IsScalarTower R A B
inst✝¹ : FinitePresentation R B
inst✝ : FiniteType R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] B
hf : Surjective ⇑f
s : Finset (MvPolynomial (Fin n) R)
hs : Ideal.span ↑s = RingHom.ker f.toRingHom
RX : Type (max w₁ 0) := MvPolynomial (Fin n) R
AX : Type (max w₂ 0) := MvPolynomial (Fin n) A
t : Finset A
ht : adjoin R ↑t = ⊤
t' : ↥t → MvPolynomial (Fin n) R
ht' : ∀ (i : ↥t), f (t' i) = (algebraMap A B) ↑i
ht'' : adjoin R (⇑(algebraMap A AX) '' ↑t ∪ Set.range MvPolynomial.X) = ⊤
g : ↥t → AX := fun x ↦ MvPolynomial.C ↑x - (MvPolynomial.map (algebraMap R A)) (t' x)
s₀✝ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
I : Ideal (MvPolynomial (Fin n) A) := RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
leI :
  Ideal.span (⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g) ≤
    RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
s₀ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
p : MvPolynomial (Fin n) R
q : MvPolynomial (Fin n) A
hq : q ∈ (Ideal.span s₀).toAddSubmonoid
hx : f p = 0
this✝ :
  (MvPolynomial.map (algebraMap R A)) p + q ∈
    (MvPolynomial.map (algebraMap R A)).range.toAddSubmonoid ⊔ (Ideal.span s₀).toAddSubmonoid
this : Ideal.span ↑s ≤ Ideal.comap (MvPolynomial.map (algebraMap R A)) (Ideal.span s₀)
⊢ (MvPolynomial.map (algebraMap R A)) p + q ∈ Ideal.span s₀

Tactic:
refine add_mem ?_ hq
      rw [hs] at this
      exact this hx

Goal state after:
Module: Mathlib.RingTheory.FinitePresentation

Goal state before:
pp: case refine_2
R : Type w₁
A : Type w₂
B : Type w₃
inst✝⁸ : CommRing R
inst✝⁷ : CommRing A
inst✝⁶ : Algebra R A
inst✝⁵ : CommRing B
inst✝⁴ : Algebra R B
inst✝³ : Algebra A B
inst✝² : IsScalarTower R A B
inst✝¹ : FinitePresentation R B
inst✝ : FiniteType R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] B
hf : Surjective ⇑f
s : Finset (MvPolynomial (Fin n) R)
hs : Ideal.span ↑s = RingHom.ker f.toRingHom
RX : Type (max w₁ 0) := MvPolynomial (Fin n) R
AX : Type (max w₂ 0) := MvPolynomial (Fin n) A
t : Finset A
ht : adjoin R ↑t = ⊤
t' : ↥t → MvPolynomial (Fin n) R
ht' : ∀ (i : ↥t), f (t' i) = (algebraMap A B) ↑i
ht'' : adjoin R (⇑(algebraMap A AX) '' ↑t ∪ Set.range MvPolynomial.X) = ⊤
g : ↥t → AX := fun x ↦ MvPolynomial.C ↑x - (MvPolynomial.map (algebraMap R A)) (t' x)
s₀✝ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
I : Ideal (MvPolynomial (Fin n) A) := RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
leI :
  Ideal.span (⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g) ≤
    RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
s₀ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
p : MvPolynomial (Fin n) R
q : MvPolynomial (Fin n) A
hq : q ∈ (Ideal.span s₀).toAddSubmonoid
hx : f p = 0
this :
  (MvPolynomial.map (algebraMap R A)) p + q ∈
    (MvPolynomial.map (algebraMap R A)).range.toAddSubmonoid ⊔ (Ideal.span s₀).toAddSubmonoid
x : RX
⊢ x ∈ ↑s → x ∈ ↑(Ideal.comap (MvPolynomial.map (algebraMap R A)) (Ideal.span s₀))

Tactic:
hx

Goal state after:
case refine_2
R : Type w₁
A : Type w₂
B : Type w₃
inst✝⁸ : CommRing R
inst✝⁷ : CommRing A
inst✝⁶ : Algebra R A
inst✝⁵ : CommRing B
inst✝⁴ : Algebra R B
inst✝³ : Algebra A B
inst✝² : IsScalarTower R A B
inst✝¹ : FinitePresentation R B
inst✝ : FiniteType R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] B
hf : Surjective ⇑f
s : Finset (MvPolynomial (Fin n) R)
hs : Ideal.span ↑s = RingHom.ker f.toRingHom
RX : Type (max w₁ 0) := MvPolynomial (Fin n) R
AX : Type (max w₂ 0) := MvPolynomial (Fin n) A
t : Finset A
ht : adjoin R ↑t = ⊤
t' : ↥t → MvPolynomial (Fin n) R
ht' : ∀ (i : ↥t), f (t' i) = (algebraMap A B) ↑i
ht'' : adjoin R (⇑(algebraMap A AX) '' ↑t ∪ Set.range MvPolynomial.X) = ⊤
g : ↥t → AX := fun x ↦ MvPolynomial.C ↑x - (MvPolynomial.map (algebraMap R A)) (t' x)
s₀✝ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
I : Ideal (MvPolynomial (Fin n) A) := RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
leI :
  Ideal.span (⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g) ≤
    RingHom.ker (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X))
s₀ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
p : MvPolynomial (Fin n) R
q : MvPolynomial (Fin n) A
hq : q ∈ (Ideal.span s₀).toAddSubmonoid
hx✝ : f p = 0
this :
  (MvPolynomial.map (algebraMap R A)) p + q ∈
    (MvPolynomial.map (algebraMap R A)).range.toAddSubmonoid ⊔ (Ideal.span s₀).toAddSubmonoid
x : RX
hx : x ∈ ↑s
⊢ x ∈ ↑(Ideal.comap (MvPolynomial.map (algebraMap R A)) (Ideal.span s₀))
Module: Mathlib.RingTheory.FinitePresentation

Goal state before:
pp: R : Type w₁
A : Type w₂
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] A
hf : Surjective ⇑f
inst✝ : FinitePresentation R A
m : ℕ
f' : MvPolynomial (Fin m) R →ₐ[R] A
hf' : Surjective ⇑f'
s : Finset (MvPolynomial (Fin m) R)
hs : Ideal.span ↑s = RingHom.ker f'.toRingHom
RXn : Type (max w₁ 0) := MvPolynomial (Fin n) R
RXm : Type (max w₁ 0) := MvPolynomial (Fin m) R
g : Fin n → MvPolynomial (Fin m) R
hg : ∀ (i : Fin n), f' (g i) = f (MvPolynomial.X i)
h : Fin m → MvPolynomial (Fin n) R
hh : ∀ (i : Fin m), f (h i) = f' (MvPolynomial.X i)
aeval_h : RXm →ₐ[R] RXn := MvPolynomial.aeval h
g' : Fin n → RXn := fun i ↦ MvPolynomial.X i - aeval_h (g i)
hh' : ∀ (x : RXm), f (aeval_h x) = f' x
s' : Set RXn := Set.range g' ∪ ⇑aeval_h '' ↑s
leI : Ideal.span s' ≤ RingHom.ker f.toRingHom
x : RXn
⊢ x ∈ RingHom.ker f.toRingHom → x ∈ Ideal.span s'

Tactic:
hx

Goal state after:
R : Type w₁
A : Type w₂
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] A
hf : Surjective ⇑f
inst✝ : FinitePresentation R A
m : ℕ
f' : MvPolynomial (Fin m) R →ₐ[R] A
hf' : Surjective ⇑f'
s : Finset (MvPolynomial (Fin m) R)
hs : Ideal.span ↑s = RingHom.ker f'.toRingHom
RXn : Type (max w₁ 0) := MvPolynomial (Fin n) R
RXm : Type (max w₁ 0) := MvPolynomial (Fin m) R
g : Fin n → MvPolynomial (Fin m) R
hg : ∀ (i : Fin n), f' (g i) = f (MvPolynomial.X i)
h : Fin m → MvPolynomial (Fin n) R
hh : ∀ (i : Fin m), f (h i) = f' (MvPolynomial.X i)
aeval_h : RXm →ₐ[R] RXn := MvPolynomial.aeval h
g' : Fin n → RXn := fun i ↦ MvPolynomial.X i - aeval_h (g i)
hh' : ∀ (x : RXm), f (aeval_h x) = f' x
s' : Set RXn := Set.range g' ∪ ⇑aeval_h '' ↑s
leI : Ideal.span s' ≤ RingHom.ker f.toRingHom
x : RXn
hx : x ∈ RingHom.ker f.toRingHom
⊢ x ∈ Ideal.span s'
Module: Mathlib.RingTheory.FinitePresentation

Goal state before:
pp: R : Type w₁
A : Type w₂
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] A
hf : Surjective ⇑f
inst✝ : FinitePresentation R A
m : ℕ
f' : MvPolynomial (Fin m) R →ₐ[R] A
hf' : Surjective ⇑f'
s : Finset (MvPolynomial (Fin m) R)
hs : Ideal.span ↑s = RingHom.ker f'.toRingHom
RXn : Type (max w₁ 0) := MvPolynomial (Fin n) R
RXm : Type (max w₁ 0) := MvPolynomial (Fin m) R
g : Fin n → MvPolynomial (Fin m) R
hg : ∀ (i : Fin n), f' (g i) = f (MvPolynomial.X i)
h : Fin m → MvPolynomial (Fin n) R
hh : ∀ (i : Fin m), f (h i) = f' (MvPolynomial.X i)
aeval_h : RXm →ₐ[R] RXn := MvPolynomial.aeval h
g' : Fin n → RXn := fun i ↦ MvPolynomial.X i - aeval_h (g i)
hh' : ∀ (x : RXm), f (aeval_h x) = f' x
s' : Set RXn := Set.range g' ∪ ⇑aeval_h '' ↑s
leI : Ideal.span s' ≤ RingHom.ker f.toRingHom
x✝ : RXm
y : RXn
hy : y ∈ (Ideal.span s').toAddSubmonoid
this : aeval_h.toRingHom x✝ + y ∈ aeval_h.range.toAddSubmonoid ⊔ (Ideal.span s').toAddSubmonoid
hx : f' x✝ = 0
x : RXm
⊢ x ∈ ↑s → x ∈ ↑(Ideal.comap aeval_h (Ideal.span s'))

Tactic:
hx

Goal state after:
R : Type w₁
A : Type w₂
inst✝³ : CommRing R
inst✝² : CommRing A
inst✝¹ : Algebra R A
n : ℕ
f : MvPolynomial (Fin n) R →ₐ[R] A
hf : Surjective ⇑f
inst✝ : FinitePresentation R A
m : ℕ
f' : MvPolynomial (Fin m) R →ₐ[R] A
hf' : Surjective ⇑f'
s : Finset (MvPolynomial (Fin m) R)
hs : Ideal.span ↑s = RingHom.ker f'.toRingHom
RXn : Type (max w₁ 0) := MvPolynomial (Fin n) R
RXm : Type (max w₁ 0) := MvPolynomial (Fin m) R
g : Fin n → MvPolynomial (Fin m) R
hg : ∀ (i : Fin n), f' (g i) = f (MvPolynomial.X i)
h : Fin m → MvPolynomial (Fin n) R
hh : ∀ (i : Fin m), f (h i) = f' (MvPolynomial.X i)
aeval_h : RXm →ₐ[R] RXn := MvPolynomial.aeval h
g' : Fin n → RXn := fun i ↦ MvPolynomial.X i - aeval_h (g i)
hh' : ∀ (x : RXm), f (aeval_h x) = f' x
s' : Set RXn := Set.range g' ∪ ⇑aeval_h '' ↑s
leI : Ideal.span s' ≤ RingHom.ker f.toRingHom
x✝ : RXm
y : RXn
hy : y ∈ (Ideal.span s').toAddSubmonoid
this : aeval_h.toRingHom x✝ + y ∈ aeval_h.range.toAddSubmonoid ⊔ (Ideal.span s').toAddSubmonoid
hx✝ : f' x✝ = 0
x : RXm
hx : x ∈ ↑s
⊢ x ∈ ↑(Ideal.comap aeval_h (Ideal.span s'))
Module: Mathlib.CategoryTheory.Limits.Shapes.RegularMono

Goal state before:
pp: C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
X Y : C
g h : X ⟶ Y
inst✝ : HasColimit (parallelPair g h)
s : Cofork g h
m : (Cofork.ofπ (coequalizer.π g h) ⋯).pt ⟶ s.pt
w : (Cofork.ofπ (coequalizer.π g h) ⋯).π ≫ m = s.π
⊢ m = colimit.desc (parallelPair g h) s

Tactic:
apply coequalizer.hom_ext

Goal state after:
C : Type u₁
inst✝¹ : Category.{v₁, u₁} C
X Y : C
g h : X ⟶ Y
inst✝ : HasColimit (parallelPair g h)
s : Cofork g h
m : (Cofork.ofπ (coequalizer.π g h) ⋯).pt ⟶ s.pt
w : (Cofork.ofπ (coequalizer.π g h) ⋯).π ≫ m = s.π
⊢ coequalizer.π g h ≫ m = coequalizer.π g h ≫ colimit.desc (parallelPair g h) s
Module: Mathlib.CategoryTheory.Limits.Shapes.Pullback.Assoc

Goal state before:
pp: C : Type u
inst✝³ : Category.{v, u} C
X₁ X₂ X₃ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₁
f₃ : X₂ ⟶ Y₂
f₄ : X₃ ⟶ Y₂
inst✝² : HasPullback f₁ f₂
inst✝¹ : HasPullback f₃ f₄
inst✝ : HasPullback (pullback.snd f₁ f₂ ≫ f₃) f₄
⊢ IsLimit
    (PullbackCone.mk (pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄)
      (pullback.lift (pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄ ≫ pullback.snd f₁ f₂)
        (pullback.snd (pullback.snd f₁ f₂ ≫ f₃) f₄) ⋯)
      ⋯)

Tactic:
apply leftSquareIsPullback _ rfl (pullbackIsPullback f₃ f₄)

Goal state after:
C : Type u
inst✝³ : Category.{v, u} C
X₁ X₂ X₃ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₁
f₃ : X₂ ⟶ Y₂
f₄ : X₃ ⟶ Y₂
inst✝² : HasPullback f₁ f₂
inst✝¹ : HasPullback f₃ f₄
inst✝ : HasPullback (pullback.snd f₁ f₂ ≫ f₃) f₄
⊢ IsLimit
    ((PullbackCone.mk (pullback.fst f₃ f₄) (pullback.snd f₃ f₄) ⋯).pasteHoriz
      (PullbackCone.mk (pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄)
        (pullback.lift (pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄ ≫ pullback.snd f₁ f₂)
          (pullback.snd (pullback.snd f₁ f₂ ≫ f₃) f₄) ⋯)
        ⋯)
      ⋯)
Module: Mathlib.CategoryTheory.Limits.Shapes.Diagonal

Goal state before:
pp: case refine_1.refine_5
C : Type u_1
inst✝⁵ : Category.{v_1, u_1} C
X Y Z : C
inst✝⁴ : HasPullbacks C
S T : C
f : X ⟶ T
g : Y ⟶ T
i : T ⟶ S
inst✝³ : HasPullback i i
inst✝² : HasPullback f g
inst✝¹ : HasPullback (f ≫ i) (g ≫ i)
inst✝ : HasPullback (diagonal i) (map (f ≫ i) (g ≫ i) i i f g (𝟙 S) ⋯ ⋯)
⊢ IsIso
    (map (diagonal i) (map (f ≫ i) (g ≫ i) i i f g (𝟙 S) ⋯ ⋯) (diagonal i)
      (map ((f ≫ inv (fst i (𝟙 S))) ≫ snd i (𝟙 S)) ((g ≫ inv (fst i (𝟙 S))) ≫ snd i (𝟙 S)) i i
        ((f ≫ inv (fst i (𝟙 S))) ≫ fst i (𝟙 S)) ((g ≫ inv (fst i (𝟙 S))) ≫ fst i (𝟙 S)) (𝟙 S) ⋯ ⋯)
      (𝟙 T) (congrHom ⋯ ⋯).hom (𝟙 (diagonalObj i)) ⋯ ⋯)

Tactic:
· infer_instance

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Shapes.Diagonal

Goal state before:
pp: case refine_2.refine_3
C : Type u_1
inst✝⁵ : Category.{v_1, u_1} C
X Y Z : C
inst✝⁴ : HasPullbacks C
S T : C
f : X ⟶ T
g : Y ⟶ T
i : T ⟶ S
inst✝³ : HasPullback i i
inst✝² : HasPullback f g
inst✝¹ : HasPullback (f ≫ i) (g ≫ i)
inst✝ : HasPullback (diagonal i) (map (f ≫ i) (g ≫ i) i i f g (𝟙 S) ⋯ ⋯)
⊢ IsIso (map (f ≫ inv (fst i (𝟙 S))) (g ≫ inv (fst i (𝟙 S))) f g (𝟙 X) (𝟙 Y) (fst i (𝟙 S)) ⋯ ⋯)

Tactic:
· infer_instance

Goal state after:
Module: Mathlib.CategoryTheory.MorphismProperty.Limits

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
P : MorphismProperty C
inst✝³ : P.IsStableUnderCobaseChange
inst✝² : P.IsStableUnderComposition
S X X' Y Y' : C
f : S ⟶ X
g : S ⟶ Y
f' : S ⟶ X'
g' : S ⟶ Y'
i₁ : X ⟶ X'
inst✝¹ : HasPushoutsAlong f
inst✝ : HasPushoutsAlong g'
i₂ : Y ⟶ Y'
h₁ : P i₁
h₂ : P i₂
e₁ : f' = f ≫ i₁
e₂ : g' = g ≫ i₂
⊢ P (pushout.map f g f' g' i₁ i₂ (𝟙 S) ⋯ ⋯)

Tactic:
by
  have : HasPushoutsAlong (Under.mk g').hom := by cat_disch
  have : pushout.map f g f' g' i₁ i₂ (𝟙 _) (by simp [e₁]) (by simp [e₂]) =
      ((pushoutSymmetry _ _).hom ≫
        ((Under.pushout f).map (Under.homMk _ e₂.symm : Under.mk g ⟶ Under.mk g')).right) ≫
        (pushoutSymmetry _ _).hom ≫
        ((Under.pushout g').map (Under.homMk _ e₁.symm : Under.mk f ⟶ Under.mk f')).right := by
    ext <;> simp
  rw [this]
  apply P.comp_mem <;> rw [P.cancel_left_of_respectsIso]
  exacts [underPushoutMap _ _ h₂, underPushoutMap _ _ h₁]

Goal state after:
Module: Mathlib.CategoryTheory.MorphismProperty.Limits

Goal state before:
pp: C : Type u
inst✝¹ : Category.{v, u} C
P : MorphismProperty C
inst✝ : P.IsStableUnderCobaseChange
X Y Z : C
f : X ⟶ Y
g : Y ⟶ Z
hf : Epi f
hcomp : P (f ≫ g)
this : g = pushout.inr (f ≫ g) f ≫ (asIso (pushout.inl (f ≫ g) f)).inv
⊢ P (pushout.inr (f ≫ g) f)

Tactic:
exact P.pushout_inr _ _ hcomp

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Constructions.FiniteProductsOfBinaryProducts

Goal state before:
pp: C : Type u
inst✝² : Category.{v, u} C
inst✝¹ : HasBinaryCoproducts C
inst✝ : HasInitial C
n : ℕ
K : Discrete (Fin n) ⥤ C
that : K ≅ Discrete.functor fun n_1 ↦ K.obj { as := n_1 } :=
  Discrete.natIso fun x ↦
    match x with
    | { as := as } => Iso.refl (K.obj { as := as })
⊢ HasColimit (Discrete.functor fun n_1 ↦ K.obj { as := n_1 })

Tactic:
apply hasCoproduct_fin

Goal state after:
Module: Mathlib.CategoryTheory.MorphismProperty.Limits

Goal state before:
pp: C : Type u
inst✝ : Category.{v, u} C
P : MorphismProperty C
⊢ P.universally.RespectsIso

Tactic:
by
  apply RespectsIso.mk
  · intro X Y Z e f hf X' Z' i₁ i₂ f' H
    have : IsPullback (𝟙 _) (i₁ ≫ e.hom) i₁ e.inv :=
      IsPullback.of_horiz_isIso
        ⟨by rw [Category.id_comp, Category.assoc, e.hom_inv_id, Category.comp_id]⟩
    exact hf _ _ _
      (by simpa only [Iso.inv_hom_id_assoc, Category.id_comp] using this.paste_horiz H)
  · intro X Y Z e f hf X' Z' i₁ i₂ f' H
    have : IsPullback (𝟙 _) i₂ (i₂ ≫ e.inv) e.inv :=
      IsPullback.of_horiz_isIso ⟨Category.id_comp _⟩
    exact hf _ _ _ (by simpa only [Category.assoc, Iso.hom_inv_id,
      Category.comp_id, Category.comp_id] using H.paste_horiz this)

Goal state after:
Module: Mathlib.CategoryTheory.Monoidal.Cartesian.Mon

Goal state before:
pp: C : Type u_1
inst✝² : Category.{v, u_1} C
inst✝¹ : CartesianMonoidalCategory C
A B : C
inst✝ : MonObj B
f : A ⟶ B
g : A ⟶ 𝟙_ C
⊢ lift f (g ≫ η) ≫ μ = f

Tactic:
by
  have := lift f g ≫= mul_one B
  rwa [lift_whiskerLeft_assoc, lift_rightUnitor_hom] at this

Goal state after:
Module: Mathlib.RingTheory.HopfAlgebra.TensorProduct

Goal state before:
pp: R : Type u_1
S : Type u_2
A : Type u_3
B : Type u_4
inst✝⁸ : CommSemiring R
inst✝⁷ : CommSemiring S
inst✝⁶ : Semiring A
inst✝⁵ : Semiring B
inst✝⁴ : Algebra R S
inst✝³ : HopfAlgebra R A
inst✝² : HopfAlgebra S B
inst✝¹ : Algebra R B
inst✝ : IsScalarTower R S B
⊢ LinearMap.mul' S (B ⊗[R] A) ∘ₗ
      LinearMap.rTensor (B ⊗[R] A) (AlgebraTensorModule.map (antipode S) (antipode R)) ∘ₗ comul =
    Algebra.linearMap S (B ⊗[R] A) ∘ₗ counit

Tactic:
ext x y

Goal state after:
R : Type u_1
S : Type u_2
A : Type u_3
B : Type u_4
inst✝⁸ : CommSemiring R
inst✝⁷ : CommSemiring S
inst✝⁶ : Semiring A
inst✝⁵ : Semiring B
inst✝⁴ : Algebra R S
inst✝³ : HopfAlgebra R A
inst✝² : HopfAlgebra S B
inst✝¹ : Algebra R B
inst✝ : IsScalarTower R S B
x : B
y : A
⊢ ((AlgebraTensorModule.curry
          (LinearMap.mul' S (B ⊗[R] A) ∘ₗ
            LinearMap.rTensor (B ⊗[R] A) (AlgebraTensorModule.map (antipode S) (antipode R)) ∘ₗ comul))
        x)
      y =
    ((AlgebraTensorModule.curry (Algebra.linearMap S (B ⊗[R] A) ∘ₗ counit)) x) y
Module: Mathlib.CategoryTheory.Monoidal.Grp

Goal state before:
pp: C : Type u₁
inst✝² : Category.{v₁, u₁} C
inst✝¹ : CartesianMonoidalCategory C
A B : C
inst✝ : GrpObj B
f : A ⟶ B
⊢ lift f (f ≫ ι) ≫ μ = toUnit A ≫ η

Tactic:
have := f ≫= right_inv B

Goal state after:
C : Type u₁
inst✝² : Category.{v₁, u₁} C
inst✝¹ : CartesianMonoidalCategory C
A B : C
inst✝ : GrpObj B
f : A ⟶ B
this : f ≫ lift (𝟙 B) ι ≫ μ = f ≫ toUnit B ≫ η
⊢ lift f (f ≫ ι) ≫ μ = toUnit A ≫ η
Module: Mathlib.RingTheory.HopfAlgebra.TensorProduct

Goal state before:
pp: R : Type u_1
S : Type u_2
A : Type u_3
B : Type u_4
inst✝⁸ : CommSemiring R
inst✝⁷ : CommSemiring S
inst✝⁶ : Semiring A
inst✝⁵ : Semiring B
inst✝⁴ : Algebra R S
inst✝³ : HopfAlgebra R A
inst✝² : HopfAlgebra S B
inst✝¹ : Algebra R B
inst✝ : IsScalarTower R S B
⊢ LinearMap.mul' S (B ⊗[R] A) ∘ₗ
      LinearMap.lTensor (B ⊗[R] A) (AlgebraTensorModule.map (antipode S) (antipode R)) ∘ₗ comul =
    Algebra.linearMap S (B ⊗[R] A) ∘ₗ counit

Tactic:
ext x y

Goal state after:
R : Type u_1
S : Type u_2
A : Type u_3
B : Type u_4
inst✝⁸ : CommSemiring R
inst✝⁷ : CommSemiring S
inst✝⁶ : Semiring A
inst✝⁵ : Semiring B
inst✝⁴ : Algebra R S
inst✝³ : HopfAlgebra R A
inst✝² : HopfAlgebra S B
inst✝¹ : Algebra R B
inst✝ : IsScalarTower R S B
x : B
y : A
⊢ ((AlgebraTensorModule.curry
          (LinearMap.mul' S (B ⊗[R] A) ∘ₗ
            LinearMap.lTensor (B ⊗[R] A) (AlgebraTensorModule.map (antipode S) (antipode R)) ∘ₗ comul))
        x)
      y =
    ((AlgebraTensorModule.curry (Algebra.linearMap S (B ⊗[R] A) ∘ₗ counit)) x) y
Module: Mathlib.CategoryTheory.Monoidal.Grp

Goal state before:
pp: C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
inst✝³ : CartesianMonoidalCategory C
A B : C
inst✝² : GrpObj A
inst✝¹ : GrpObj B
f : A ⟶ B
inst✝ : IsMonHom f
⊢ lift f (ι ≫ f) ≫ μ = toUnit A ≫ η

Tactic:
have := right_inv A =≫ f
  rwa [assoc, IsMonHom.mul_hom, assoc, IsMonHom.one_hom, lift_map_assoc, id_comp] at this

Goal state after:
Module: Mathlib.Logic.Equiv.Multiset

Goal state before:
pp: α : Type u_1
inst✝ : Encodable α
s : Multiset α
⊢ decodeMultiset (encodeMultiset s) = some s

Tactic:
by simp [encodeMultiset, decodeMultiset, encodek]

Goal state after:
Module: Mathlib.LinearAlgebra.Dual.Basis

Goal state before:
pp: R : Type uR
M : Type uM
ι : Type uι
inst✝³ : CommSemiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : DecidableEq ι
b : Basis ι R M
m : M
a : b.toDual m = 0
⊢ b.toDual m = b.toDual 0

Tactic:
map_zero

Goal state after:
R : Type uR
M : Type uM
ι : Type uι
inst✝³ : CommSemiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : DecidableEq ι
b : Basis ι R M
m : M
a : b.toDual m = 0
⊢ b.toDual m = 0
Module: Mathlib.LinearAlgebra.Dual.Basis

Goal state before:
pp: R : Type uR
M : Type uM
ι : Type uι
inst✝⁴ : CommSemiring R
inst✝³ : AddCommMonoid M
inst✝² : Module R M
inst✝¹ : DecidableEq ι
b : Basis ι R M
inst✝ : Finite ι
l : Dual R M
i : ι
⊢ (b.dualBasis.repr l) i = l (b i)

Tactic:
← linearCombination_dualBasis b,

Goal state after:
R : Type uR
M : Type uM
ι : Type uι
inst✝⁴ : CommSemiring R
inst✝³ : AddCommMonoid M
inst✝² : Module R M
inst✝¹ : DecidableEq ι
b : Basis ι R M
inst✝ : Finite ι
l : Dual R M
i : ι
⊢ ((Finsupp.linearCombination R ⇑b.dualBasis) (b.dualBasis.repr l)) (b i) = l (b i)
Module: Mathlib.LinearAlgebra.Dual.Basis

Goal state before:
pp: R : Type uR
M : Type uM
ι : Type uι
inst✝³ : CommSemiring R
inst✝² : AddCommMonoid M
inst✝¹ : Module R M
inst✝ : Finite ι
b : Basis ι R M
f : ι →₀ R
i : ι
⊢ ((Finsupp.linearCombination R b.coord) f) (b i) = f i

Tactic:
by
  have := Classical.decEq ι
  rw [← coe_dualBasis, linearCombination_dualBasis]

Goal state after:
Module: Mathlib.LinearAlgebra.Dual.Basis

Goal state before:
pp: R : Type u_1
M : Type u_2
ι : Type u_3
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
e : ι → M
ε : ι → Dual R M
h : DualBases e ε
l : ι →₀ R
i : ι
⊢ (ε i) (lc e l) = l i

Tactic:
by
  rw [lc, map_finsuppSum, Finsupp.sum_eq_single i (g := fun a b ↦ (ε i) (b • e a))]
  · simp [h.eval_same, smul_eq_mul]
  · intro q _ q_ne
    simp [h.eval_of_ne q_ne.symm, smul_eq_mul]
  · simp

Goal state after:
Module: Mathlib.LinearAlgebra.Dimension.RankNullity

Goal state before:
pp: R : Type u_1
M : Type u
M' : Type v
inst✝⁵ : Ring R
inst✝⁴ : AddCommGroup M
inst✝³ : AddCommGroup M'
inst✝² : Module R M
inst✝¹ : Module R M'
inst✝ : HasRankNullity.{u, u_1} R
f : M →ₗ[R] M'
p : Submodule R M'
f' : ↥(comap f p) →ₗ[R] ↥p := f.restrict ⋯
hk : Module.rank R ↥f'.ker ≤ Module.rank R ↥f.ker
hr : Module.rank R ↥f'.range ≤ Module.rank R ↥p
⊢ lift.{v, u} (Module.rank R ↥(comap f p)) ≤ lift.{u, v} (Module.rank R ↥p) + lift.{v, u} (Module.rank R ↥f.ker)

Tactic:
rw [← f'.lift_rank_range_add_rank_ker]

Goal state after:
R : Type u_1
M : Type u
M' : Type v
inst✝⁵ : Ring R
inst✝⁴ : AddCommGroup M
inst✝³ : AddCommGroup M'
inst✝² : Module R M
inst✝¹ : Module R M'
inst✝ : HasRankNullity.{u, u_1} R
f : M →ₗ[R] M'
p : Submodule R M'
f' : ↥(comap f p) →ₗ[R] ↥p := f.restrict ⋯
hk : Module.rank R ↥f'.ker ≤ Module.rank R ↥f.ker
hr : Module.rank R ↥f'.range ≤ Module.rank R ↥p
⊢ lift.{u, v} (Module.rank R ↥f'.range) + lift.{v, u} (Module.rank R ↥f'.ker) ≤
    lift.{u, v} (Module.rank R ↥p) + lift.{v, u} (Module.rank R ↥f.ker)