mathlib-initiative/mathlib-tactics huggingface dataset:
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))
x : MvPolynomial (Fin n) A
hx : (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X)) x = 0
s₀ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
⊢ x ∈ (MvPolynomial.map (algebraMap R A)).range.toAddSubmonoid ⊔ (Ideal.span s₀).toAddSubmonoid

Tactic:
have : x ∈ (⊤ : Subalgebra R AX) := trivial

Goal state after:
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))
x : MvPolynomial (Fin n) A
hx : (MvPolynomial.aeval (⇑f ∘ MvPolynomial.X)) x = 0
s₀ : Set (MvPolynomial (Fin n) A) := ⇑(MvPolynomial.map (algebraMap R A)) '' ↑s ∪ Set.range g
this : x ∈ ⊤
⊢ x ∈ (MvPolynomial.map (algebraMap R A)).range.toAddSubmonoid ⊔ (Ideal.span s₀).toAddSubmonoid
Module: Mathlib.CategoryTheory.Limits.Shapes.Grothendieck

Goal state before:
pp: case w_fiber
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 Y Z : C
f : X ⟶ Y
g : Y ⟶ Z
d : ↑(F.obj X)
⊢ eqToHom ⋯ = eqToHom ⋯ ≫ (F.map (𝟙 Z)).toFunctor.map (eqToHom ⋯) ≫ eqToHom ⋯

Tactic:
conv_rhs => enter [2, 1]; rw [eqToHom_map (F.map (𝟙 Z)).toFunctor]

Goal state after:
case w_fiber
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 Y Z : C
f : X ⟶ Y
g : Y ⟶ Z
d : ↑(F.obj X)
⊢ eqToHom ⋯ = eqToHom ⋯ ≫ eqToHom ⋯ ≫ eqToHom ⋯
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
hm : ∀ (j : Grothendieck F), (coconeOfCoconeFiberwiseColimit c).ι.app j ≫ m = s.ι.app j
X : C
⊢ c.ι.app X ≫ m =
    c.ι.app X ≫
      hc.desc
        { pt := s.pt,
          ι :=
            { app := fun X ↦ colimit.desc (Grothendieck.ι F X ⋙ G) (Cocone.whisker (Grothendieck.ι F X) s),
              naturality := ⋯ } }

Tactic:
simp only [fiberwiseColimit_obj, IsColimit.fac]
    simp only [coconeOfCoconeFiberwiseColimit_pt, Functor.const_obj_obj,
      coconeOfCoconeFiberwiseColimit_ι_app, Category.assoc] at hm
    ext d
    simp [hm ⟨X, d⟩]

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

Goal state before:
pp: case h₁
C : Type u₁
inst✝³ : Category.{v₁, u₁} C
D : Type u₂
inst✝² : Category.{v₂, u₂} D
F : C ⥤ D
inst✝¹ : F.Final
E : Type u₃
inst✝ : Category.{v₃, u₃} E
G : D ⥤ E
c : Cocone (F ⋙ G)
X : D
Y : C
f : X ⟶ F.obj Y
⊢ ∀ (X₁ X₂ : C) (k₁ : X ⟶ F.obj X₁) (k₂ : X ⟶ F.obj X₂) (f_1 : X₁ ⟶ X₂),
    k₁ ≫ F.map f_1 = k₂ → G.map k₁ ≫ c.ι.app X₁ = G.map f ≫ c.ι.app Y → G.map k₂ ≫ c.ι.app X₂ = G.map f ≫ c.ι.app Y

pp: case h₂
C : Type u₁
inst✝³ : Category.{v₁, u₁} C
D : Type u₂
inst✝² : Category.{v₂, u₂} D
F : C ⥤ D
inst✝¹ : F.Final
E : Type u₃
inst✝ : Category.{v₃, u₃} E
G : D ⥤ E
c : Cocone (F ⋙ G)
X : D
Y : C
f : X ⟶ F.obj Y
⊢ ∀ (X₁ X₂ : C) (k₁ : X ⟶ F.obj X₁) (k₂ : X ⟶ F.obj X₂) (f_1 : X₁ ⟶ X₂),
    k₁ ≫ F.map f_1 = k₂ → G.map k₂ ≫ c.ι.app X₂ = G.map f ≫ c.ι.app Y → G.map k₁ ≫ c.ι.app X₁ = G.map f ≫ c.ι.app Y

Tactic:
· intro _ _ _ _ _ h₁ h₂
    simp [← h₁, ← Functor.comp_map, c.ι.naturality, h₂]

Goal state after:
case h₂
C : Type u₁
inst✝³ : Category.{v₁, u₁} C
D : Type u₂
inst✝² : Category.{v₂, u₂} D
F : C ⥤ D
inst✝¹ : F.Final
E : Type u₃
inst✝ : Category.{v₃, u₃} E
G : D ⥤ E
c : Cocone (F ⋙ G)
X : D
Y : C
f : X ⟶ F.obj Y
⊢ ∀ (X₁ X₂ : C) (k₁ : X ⟶ F.obj X₁) (k₂ : X ⟶ F.obj X₂) (f_1 : X₁ ⟶ X₂),
    k₁ ≫ F.map f_1 = k₂ → G.map k₂ ≫ c.ι.app X₂ = G.map f ≫ c.ι.app Y → G.map k₁ ≫ c.ι.app X₁ = G.map f ≫ c.ι.app Y
Module: Mathlib.CategoryTheory.Limits.Shapes.RegularMono

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
X Y X' Y' : C
f : X ⟶ Y
g : X' ⟶ Y'
e : Arrow.mk f ≅ Arrow.mk g
h : RegularEpi f
⊢ (h.left ≫ Arrow.Hom.left e.hom) ≫ g = (h.right ≫ Arrow.Hom.left e.hom) ≫ g

Tactic:
by
    simp only [Category.assoc, Arrow.w_mk_right, Arrow.mk_hom]
    rw [reassoc_of% h.w]

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Shapes.Pullback.Assoc

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
X₁ X₂ X₃ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₁
f₃ : X₂ ⟶ Y₂
f₄ : X₃ ⟶ Y₂
inst✝³ : HasPullback f₁ f₂
inst✝² : HasPullback f₃ f₄
inst✝¹ : HasPullback (pullback.snd f₁ f₂ ≫ f₃) f₄
inst✝ : HasPullback f₁ (pullback.fst f₃ f₄ ≫ f₂)
⊢ pullback.lift (pullback.fst f₁ (pullback.fst f₃ f₄ ≫ f₂))
        (pullback.snd f₁ (pullback.fst f₃ f₄ ≫ f₂) ≫ pullback.fst f₃ f₄) ⋯ ≫
      pullback.fst f₁ f₂ =
    pullback.fst f₁ (pullback.fst f₃ f₄ ≫ f₂)

Tactic:
· exact pullback.lift_fst _ _ _

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

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
P : ObjectProperty C
h : ∀ (d : C), ¬P d → IsConnected (CostructuredArrow P.ι d)
d : C
hd : P d
this : Nonempty (CostructuredArrow P.ι d)
j₁ j₂ : CostructuredArrow P.ι d
⊢ CostructuredArrow P.ι d

Tactic:
exact CostructuredArrow.mk (Y := ⟨d, hd⟩) (𝟙 _)

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

Goal state before:
pp: C : Type u₁
inst✝ : Category.{v₁, u₁} C
P : ObjectProperty C
h : ∀ (d : C), ¬P d → IsConnected (CostructuredArrow P.ι d)
d : C
⊢ IsConnected (CostructuredArrow P.ι d)

Tactic:
by_cases hd : P d
  · have : Nonempty (CostructuredArrow P.ι d) := ⟨⟨d, hd⟩, ⟨⟨⟩⟩, 𝟙 _⟩
    refine zigzag_isConnected (fun j₁ j₂ ↦ Zigzag.trans
      (j₂ := by exact CostructuredArrow.mk (Y := ⟨d, hd⟩) (𝟙 _)) (.of_hom ?_) (.of_inv ?_))
    · exact CostructuredArrow.homMk (InducedCategory.homMk j₁.hom)
    · exact CostructuredArrow.homMk (InducedCategory.homMk j₂.hom)
  · exact h d hd

Goal state after:
Module: Mathlib.CategoryTheory.Limits.Shapes.Pullback.Assoc

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
X₁ X₂ X₃ Y₁ Y₂ : C
f₁ : X₁ ⟶ Y₁
f₂ : X₂ ⟶ Y₁
f₃ : X₂ ⟶ Y₂
f₄ : X₃ ⟶ Y₂
inst✝³ : HasPullback f₁ f₂
inst✝² : HasPullback f₃ f₄
inst✝¹ : HasPullback (pullback.snd f₁ f₂ ≫ f₃) f₄
inst✝ : HasPullback f₁ (pullback.fst f₃ f₄ ≫ f₂)
⊢ pullback.lift (pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄ ≫ pullback.snd f₁ f₂)
        (pullback.snd (pullback.snd f₁ f₂ ≫ f₃) f₄) ⋯ ≫
      pullback.fst f₃ f₄ =
    pullback.fst (pullback.snd f₁ f₂ ≫ f₃) f₄ ≫ pullback.snd f₁ f₂

Tactic:
· exact pullback.lift_fst _ _ _

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

Goal state before:
pp: C : Type u_1
inst✝¹ : Category.{v_1, u_1} C
X Y : C
f : X ⟶ Y
inst✝ : HasPullback f f
H : IsIso (diagonal f)
Z✝ : C
x✝¹ x✝ : Z✝ ⟶ X
e : x✝¹ ≫ f = x✝ ≫ f
⊢ x✝¹ = x✝

Tactic:
rw [← lift_fst _ _ e, (cancel_epi (g := fst f f) (h := snd f f)
    (diagonal f)).mp (by simp), lift_snd]

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

Goal state before:
pp: C : Type u
inst✝² : Category.{v, u} C
R X Y : C
f : X ⟶ Y
a : R ⟶ X
inst✝¹ : IsIso a
inst✝ : Mono f
⊢ IsKernelPair f a a

Tactic:
change IsPullback _ _ _ _

Goal state after:
C : Type u
inst✝² : Category.{v, u} C
R X Y : C
f : X ⟶ Y
a : R ⟶ X
inst✝¹ : IsIso a
inst✝ : Mono f
⊢ IsPullback a a f f
Module: Mathlib.CategoryTheory.Limits.Constructions.FiniteProductsOfBinaryProducts

Goal state before:
pp: C : Type u
inst✝⁴ : Category.{v, u} C
D : Type u'
inst✝³ : Category.{v', u'} D
F : C ⥤ D
inst✝² : PreservesLimitsOfShape (Discrete WalkingPair) F
inst✝¹ : PreservesLimitsOfShape (Discrete PEmpty.{1}) F
inst✝ : HasFiniteProducts C
n : ℕ
this : ∀ (f : Fin n → C), PreservesLimit (Discrete.functor f) F
f : Fin (n + 1) → C
⊢ IsLimit
    (F.mapCone
      (extendFan (limit.cone (Discrete.functor fun i ↦ f i.succ))
        (limit.cone (pair (f 0) (limit.cone (Discrete.functor fun i ↦ f i.succ)).pt))))

Tactic:
apply (isLimitMapConeFanMkEquiv _ _ _).symm _

Goal state after:
C : Type u
inst✝⁴ : Category.{v, u} C
D : Type u'
inst✝³ : Category.{v', u'} D
F : C ⥤ D
inst✝² : PreservesLimitsOfShape (Discrete WalkingPair) F
inst✝¹ : PreservesLimitsOfShape (Discrete PEmpty.{1}) F
inst✝ : HasFiniteProducts C
n : ℕ
this : ∀ (f : Fin n → C), PreservesLimit (Discrete.functor f) F
f : Fin (n + 1) → C
⊢ IsLimit
    (Fan.mk (F.obj (limit.cone (pair (f 0) (limit.cone (Discrete.functor fun i ↦ f i.succ)).pt)).pt) fun j ↦
      F.map
        (Fin.cases (BinaryFan.fst (limit.cone (pair (f 0) (limit.cone (Discrete.functor fun i ↦ f i.succ)).pt)))
          (fun i ↦
            BinaryFan.snd (limit.cone (pair (f 0) (limit.cone (Discrete.functor fun i ↦ f i.succ)).pt)) ≫
              (limit.cone (Discrete.functor fun i ↦ f i.succ)).π.app { as := i })
          j))
Module: Mathlib.CategoryTheory.ObjectProperty.LimitsOfShape

Goal state before:
pp: C : Type u_1
D : Type u_2
inst✝³ : Category.{v_1, u_1} C
inst✝² : Category.{v_2, u_2} D
P : ObjectProperty C
J : Type u'
inst✝¹ : Category.{v', u'} J
J' : Type u''
inst✝ : Category.{v'', u''} J'
X : C
p : P.LimitOfShape J X
j : J
⊢ X ⟶ P.ι.obj { obj := p.diag.obj j, property := ⋯ }

Tactic:
by exact p.π.app j

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

Goal state before:
pp: case h₀.h₀.h₀
C : Type u_1
inst✝² : Category.{v_1, u_1} C
X✝ Y✝ Z : C
inst✝¹ : HasPullbacks C
X Y S X' Y' S' : C
f : X ⟶ S
g : Y ⟶ S
f' : X' ⟶ S'
g' : Y' ⟶ S'
i₁ : X ⟶ X'
i₂ : Y ⟶ Y'
i₃ : S ⟶ S'
e₁ : f ≫ i₃ = i₁ ≫ f'
e₂ : g ≫ i₃ = i₂ ≫ g'
inst✝ : Mono i₃
⊢ (((lift (fst (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (fst f' g') i₁)
              (snd (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (snd f' g') i₂) ⋯ ≫
            lift (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (fst f g) ⋯) (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (snd f g) ⋯)
              ⋯) ≫
          fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      fst f' g' =
    ((𝟙 (pullback (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫ fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      fst f' g'

pp: case h₁
C : Type u_1
inst✝² : Category.{v_1, u_1} C
X✝ Y✝ Z : C
inst✝¹ : HasPullbacks C
X Y S X' Y' S' : C
f : X ⟶ S
g : Y ⟶ S
f' : X' ⟶ S'
g' : Y' ⟶ S'
i₁ : X ⟶ X'
i₂ : Y ⟶ Y'
i₃ : S ⟶ S'
e₁ : f ≫ i₃ = i₁ ≫ f'
e₂ : g ≫ i₃ = i₂ ≫ g'
inst✝ : Mono i₃
⊢ (((lift (fst (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (fst f' g') i₁)
              (snd (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (snd f' g') i₂) ⋯ ≫
            lift (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (fst f g) ⋯) (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (snd f g) ⋯)
              ⋯) ≫
          fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      snd f' g' =
    ((𝟙 (pullback (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫ fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      snd f' g'

Tactic:
· simp only [Category.assoc, lift_fst, lift_fst_assoc, Category.id_comp]
          rw [condition]

Goal state after:
case h₁
C : Type u_1
inst✝² : Category.{v_1, u_1} C
X✝ Y✝ Z : C
inst✝¹ : HasPullbacks C
X Y S X' Y' S' : C
f : X ⟶ S
g : Y ⟶ S
f' : X' ⟶ S'
g' : Y' ⟶ S'
i₁ : X ⟶ X'
i₂ : Y ⟶ Y'
i₃ : S ⟶ S'
e₁ : f ≫ i₃ = i₁ ≫ f'
e₂ : g ≫ i₃ = i₂ ≫ g'
inst✝ : Mono i₃
⊢ (((lift (fst (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (fst f' g') i₁)
              (snd (fst (fst f' g') i₁) (fst (snd f' g') i₂) ≫ snd (snd f' g') i₂) ⋯ ≫
            lift (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (fst f g) ⋯) (lift (map f g f' g' i₁ i₂ i₃ e₁ e₂) (snd f g) ⋯)
              ⋯) ≫
          fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      snd f' g' =
    ((𝟙 (pullback (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫ fst (fst (fst f' g') i₁) (fst (snd f' g') i₂)) ≫
        fst (fst f' g') i₁) ≫
      snd f' g'
Module: Mathlib.CategoryTheory.Monoidal.Cartesian.Basic

Goal state before:
pp: C✝ : Type u
inst✝⁴ : Category.{v, u} C✝
C : Type u
inst✝³ : Category.{v, u} C
inst✝² : CartesianMonoidalCategory C
P : ObjectProperty C
inst✝¹ : P.IsClosedUnderLimitsOfShape (Discrete PEmpty.{1})
inst✝ : P.IsClosedUnderLimitsOfShape (Discrete WalkingPair)
X Y : P.FullSubcategory
⊢ ObjectProperty.homMk (snd X.obj Y.obj) =
    (IsTerminal.ofUniqueHom (fun X ↦ ObjectProperty.homMk (toUnit X.obj)) ⋯).from X ▷ Y ≫ (λ_ Y).hom

Tactic:
ext; exact snd_def X.1 Y.1

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

Goal state before:
pp: C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
inst✝³ : CartesianMonoidalCategory C
D : Type u₂
inst✝² : Category.{v₂, u₂} D
inst✝¹ : CartesianMonoidalCategory D
F : C ⥤ D
inst✝ : F.OplaxMonoidal
X Y : C
⊢ δ F X Y ≫ F.map (toUnit X) ▷ F.obj Y ≫ snd (F.obj (𝟙_ C)) (F.obj Y) = F.map (toUnit X ▷ Y) ≫ F.map (λ_ Y).hom

Tactic:
δ_natural_left_assoc

Goal state after:
C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
inst✝³ : CartesianMonoidalCategory C
D : Type u₂
inst✝² : Category.{v₂, u₂} D
inst✝¹ : CartesianMonoidalCategory D
F : C ⥤ D
inst✝ : F.OplaxMonoidal
X Y : C
⊢ F.map (toUnit X ▷ Y) ≫ δ F (𝟙_ C) Y ≫ snd (F.obj (𝟙_ C)) (F.obj Y) = F.map (toUnit X ▷ Y) ≫ F.map (λ_ Y).hom
Module: Mathlib.Data.W.Basic

Goal state before:
pp: case succ.succ
α : Type u_1
β : α → Type u_2
a b : α
ha : Nonempty (β a)
he : IsEmpty (β b)
hf : Finite (WType β)
hba : b ≠ a
n : ℕ
ih :
  ∀ ⦃m : ℕ⦄,
    (fun n ↦
            have this := Nat.recOn n (mk b he.elim') fun x ih ↦ mk a fun x ↦ ih;
            this)
          n =
        (fun n ↦
            have this := Nat.recOn n (mk b he.elim') fun x ih ↦ mk a fun x ↦ ih;
            this)
          m →
      n = m
m : ℕ
h :
  (fun n ↦
        have this := Nat.recOn n (mk b he.elim') fun x ih ↦ mk a fun x ↦ ih;
        this)
      (n + 1) =
    (fun n ↦
        have this := Nat.recOn n (mk b he.elim') fun x ih ↦ mk a fun x ↦ ih;
        this)
      (m + 1)
⊢ n + 1 = m + 1

Tactic:
refine congr_arg Nat.succ (ih ?_)
        simp_all [funext_iff]

Goal state after:
Module: Mathlib.CategoryTheory.Monoidal.Rigid.Basic

Goal state before:
pp: C : Type u₁
inst✝³ : Category.{v₁, u₁} C
inst✝² : MonoidalCategory C
X₁ X₂ Y₁ Y₂ : C
inst✝¹ : ExactPairing X₁ Y₁
inst✝ : ExactPairing X₂ Y₂
⊢ (Y₂ ⊗ Y₁) ◁ (η_ X₁ Y₁ ⊗≫ (X₁ ◁ η_ X₂ Y₂) ▷ Y₁ ⊗≫ 𝟙 ((X₁ ⊗ X₂) ⊗ Y₂ ⊗ Y₁)) ≫
      (α_ (Y₂ ⊗ Y₁) (X₁ ⊗ X₂) (Y₂ ⊗ Y₁)).inv ≫ (𝟙 ((Y₂ ⊗ Y₁) ⊗ X₁ ⊗ X₂) ⊗≫ Y₂ ◁ ε_ X₁ Y₁ ▷ X₂ ⊗≫ ε_ X₂ Y₂) ▷ (Y₂ ⊗ Y₁) =
    (ρ_ (Y₂ ⊗ Y₁)).hom ≫ (λ_ (Y₂ ⊗ Y₁)).inv

Tactic:
by
    calc
      _ = (Y₂ ⊗ Y₁) ◁ η_ X₁ Y₁ ⊗≫
          (Y₂ ⊗ Y₁) ◁ (X₁ ◁ η_ X₂ Y₂) ▷ Y₁ ⊗≫
          (Y₂ ◁ (ε_ X₁ Y₁ ▷ X₂)) ▷ (Y₂ ⊗ Y₁) ⊗≫
          ε_ X₂ Y₂ ▷ (Y₂ ⊗ Y₁) := by monoidal
      -- Group η₂ and ε₁ so they compose with ≫ (both act on the Y₁ ⊗ X₁ factor):
      --
      --   Y₂  Y₁      ╭── X₁ ────────────╮
      --   │    │      │    ╭── X₂ ───╮   │
      --   │    │      │    │         │   │
      --   │    ╰──ε₁──╯    │         │   │
      --   │                │         │   │
      --   ╰────── ε₂ ──────╯         │   │
      --                              Y₂  Y₁
      --
      _ = (Y₂ ⊗ Y₁) ◁ η_ X₁ Y₁ ⊗≫
          Y₂ ◁ ((Y₁ ⊗ X₁) ◁ η_ X₂ Y₂ ≫ ε_ X₁ Y₁ ▷ (X₂ ⊗ Y₂)) ▷ Y₁ ⊗≫
          ε_ X₂ Y₂ ▷ (Y₂ ⊗ Y₁) := by monoidal
      -- Slide the η₂ cup past the ε₁ cap (whisker_exchange), separating the
      -- two zigzags into independent snakes:
      --
      --   Y₂   Y₁
      --   │    │   ╭─X₁──╮
      --   │    │   │     │
      --   │    ╰───╯     │       ← snake for (X₁, Y₁)
      --   │              │
      --   │  ╭─X₂──╮     │
      --   │  │     │     │
      --   ╰──╯     │     │       ← snake for (X₂, Y₂)
      --            Y₂    Y₁
      --
      _ = (Y₂ ⊗ Y₁) ◁ η_ X₁ Y₁ ⊗≫
          Y₂ ◁ (ε_ X₁ Y₁ ▷ (𝟙_ C) ≫ (𝟙_ C) ◁ η_ X₂ Y₂) ▷ Y₁ ⊗≫
          ε_ X₂ Y₂ ▷ (Y₂ ⊗ Y₁) := by
        rw [whisker_exchange]
      -- Separate into two snakes and cancel each.
      _ = 𝟙 _ ⊗≫ Y₂ ◁ (Y₁ ◁ η_ X₁ Y₁ ⊗≫ ε_ X₁ Y₁ ▷ Y₁) ⊗≫
          (Y₂ ◁ η_ X₂ Y₂ ⊗≫ ε_ X₂ Y₂ ▷ Y₂) ▷ Y₁ ⊗≫ 𝟙 _ := by monoidal
      _ = _ := by rw [coevaluation_evaluation'', coevaluation_evaluation'']; monoidal

Goal state after:
Module: Mathlib.CategoryTheory.Monoidal.Rigid.Basic

Goal state before:
pp: C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
inst✝³ : MonoidalCategory C
X Y Z : C
inst✝² : HasRightDual X
inst✝¹ : HasRightDual Y
inst✝ : HasRightDual Z
f : X ⟶ Y
g : Y ⟶ Z
⊢ η_ Y Yᘁ ≫ (g ⊗ₘ (ρ_ Yᘁ).inv ≫ Yᘁ ◁ η_ X Xᘁ ≫ Yᘁ ◁ f ▷ Xᘁ ≫ (α_ Yᘁ Y Xᘁ).inv ≫ ε_ Y Yᘁ ▷ Xᘁ ≫ (λ_ Xᘁ).hom) =
    𝟙 (𝟙_ C) ⊗≫ (η_ Y Yᘁ ▷ 𝟙_ C ≫ (Y ⊗ Yᘁ) ◁ η_ X Xᘁ) ⊗≫ Y ◁ Yᘁ ◁ f ▷ Xᘁ ⊗≫ Y ◁ ε_ Y Yᘁ ▷ Xᘁ ⊗≫ g ▷ Xᘁ ⊗≫ 𝟙 (Z ⊗ Xᘁ)

Tactic:
rw [tensorHom_def']

Goal state after:
C : Type u₁
inst✝⁴ : Category.{v₁, u₁} C
inst✝³ : MonoidalCategory C
X Y Z : C
inst✝² : HasRightDual X
inst✝¹ : HasRightDual Y
inst✝ : HasRightDual Z
f : X ⟶ Y
g : Y ⟶ Z
⊢ η_ Y Yᘁ ≫ Y ◁ ((ρ_ Yᘁ).inv ≫ Yᘁ ◁ η_ X Xᘁ ≫ Yᘁ ◁ f ▷ Xᘁ ≫ (α_ Yᘁ Y Xᘁ).inv ≫ ε_ Y Yᘁ ▷ Xᘁ ≫ (λ_ Xᘁ).hom) ≫ g ▷ Xᘁ =
    𝟙 (𝟙_ C) ⊗≫ (η_ Y Yᘁ ▷ 𝟙_ C ≫ (Y ⊗ Yᘁ) ◁ η_ X Xᘁ) ⊗≫ Y ◁ Yᘁ ◁ f ▷ Xᘁ ⊗≫ Y ◁ ε_ Y Yᘁ ▷ Xᘁ ⊗≫ g ▷ Xᘁ ⊗≫ 𝟙 (Z ⊗ Xᘁ)
Module: Mathlib.LinearAlgebra.Dimension.ErdosKaplansky

Goal state before:
pp: K : Type u
inst✝² : DivisionRing K
V : Type v
inst✝¹ : AddCommGroup V
inst✝ : Module K V
h : ℵ₀ ≤ Module.rank K V
⊢ lift.{u, v} (Module.rank K V) < Module.rank Kᵐᵒᵖ (V →ₗ[K] K)

Tactic:
obtain ⟨⟨ι, b⟩⟩ := Module.Free.exists_basis (R := K) (M := V)
  rw [← b.mk_eq_rank'', rank_dual_eq_card_dual_of_aleph0_le_rank' h,
      ← (b.constr ℕ (M' := K)).toEquiv.cardinal_eq, mk_arrow]
  apply cantor'
  rw [one_lt_lift_iff, one_lt_iff_nontrivial]
  infer_instance

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

Goal state before:
pp: K : Type u
V V₁ V₂ V₃ : Type v
inst✝⁸ : DivisionRing K
inst✝⁷ : AddCommGroup V
inst✝⁶ : Module K V
inst✝⁵ : AddCommGroup V₁
inst✝⁴ : Module K V₁
inst✝³ : AddCommGroup V₂
inst✝² : Module K V₂
inst✝¹ : AddCommGroup V₃
inst✝ : Module K V₃
db : V₂ →ₗ[K] V
eb : V₃ →ₗ[K] V
cd : V₁ →ₗ[K] V₂
ce : V₁ →ₗ[K] V₃
hde : ⊤ ≤ db.range ⊔ eb.range
hgd : cd.ker = ⊥
eq : db ∘ₗ cd = eb ∘ₗ ce
eq₂ : ∀ (d : V₂) (e : V₃), db d = eb e → ∃ c, cd c = d ∧ ce c = e
hf : Surjective ⇑(db.coprod eb)
| Module.rank K V + Module.rank K V₁ = Module.rank K V₂ + Module.rank K V₃

Tactic:
rhs
    rw [← rank_prod', rank_eq_of_surjective hf]

Goal state after:
K : Type u
V V₁ V₂ V₃ : Type v
inst✝⁸ : DivisionRing K
inst✝⁷ : AddCommGroup V
inst✝⁶ : Module K V
inst✝⁵ : AddCommGroup V₁
inst✝⁴ : Module K V₁
inst✝³ : AddCommGroup V₂
inst✝² : Module K V₂
inst✝¹ : AddCommGroup V₃
inst✝ : Module K V₃
db : V₂ →ₗ[K] V
eb : V₃ →ₗ[K] V
cd : V₁ →ₗ[K] V₂
ce : V₁ →ₗ[K] V₃
hde : ⊤ ≤ db.range ⊔ eb.range
hgd : cd.ker = ⊥
eq : db ∘ₗ cd = eb ∘ₗ ce
eq₂ : ∀ (d : V₂) (e : V₃), db d = eb e → ∃ c, cd c = d ∧ ce c = e
hf : Surjective ⇑(db.coprod eb)
| Module.rank K V + Module.rank K ↥(db.coprod eb).ker
Module: Mathlib.LinearAlgebra.Dimension.RankNullity

Goal state before:
pp: R : Type u_1
M : Type u
inst✝³ : Ring R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : HasRankNullity.{u, u_1} R
s t : Submodule R M
⊢ Module.rank R (↥(s ⊔ t) ⧸ comap (s ⊔ t).subtype t) + Module.rank R ↥((s ⊔ t) ⊓ t) + Module.rank R ↥(s ⊓ t) =
    Module.rank R (↥(s ⊔ t) ⧸ comap (s ⊔ t).subtype t) + Module.rank R ↥(s ⊓ t) + Module.rank R ↥((s ⊔ t) ⊓ t)

Tactic:
add_right_comm

Goal state after:
R : Type u_1
M : Type u
inst✝³ : Ring R
inst✝² : AddCommGroup M
inst✝¹ : Module R M
inst✝ : HasRankNullity.{u, u_1} R
s t : Submodule R M
⊢ Module.rank R (↥(s ⊔ t) ⧸ comap (s ⊔ t).subtype t) + Module.rank R ↥(s ⊓ t) + Module.rank R ↥((s ⊔ t) ⊓ t) =
    Module.rank R (↥(s ⊔ t) ⧸ comap (s ⊔ t).subtype t) + Module.rank R ↥(s ⊓ t) + Module.rank R ↥((s ⊔ t) ⊓ t)
Module: Mathlib.LinearAlgebra.FiniteDimensional.Lemmas

Goal state before:
pp: K : Type u
V : Type v
inst✝⁵ : DivisionRing K
inst✝⁴ : AddCommGroup V
inst✝³ : Module K V
V₂ : Type v'
inst✝² : AddCommGroup V₂
inst✝¹ : Module K V₂
inst✝ : FiniteDimensional K V
f : V →ₗ[K] V₂
⊢ finrank K ↥f.range + finrank K ↥f.ker = finrank K V

Tactic:
rw [← f.quotKerEquivRange.finrank_eq]

Goal state after:
K : Type u
V : Type v
inst✝⁵ : DivisionRing K
inst✝⁴ : AddCommGroup V
inst✝³ : Module K V
V₂ : Type v'
inst✝² : AddCommGroup V₂
inst✝¹ : Module K V₂
inst✝ : FiniteDimensional K V
f : V →ₗ[K] V₂
⊢ finrank K (V ⧸ f.ker) + finrank K ↥f.ker = finrank K V
Module: Mathlib.LinearAlgebra.FiniteDimensional.Lemmas

Goal state before:
pp: K : Type u
V : Type v
inst✝³ : DivisionRing K
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : FiniteDimensional K V
f : End K V
m : ℕ
hm : finrank K V ≤ m
k : ℕ
h_k_le : k ≤ finrank K V
hk : LinearMap.ker (f ^ k) = LinearMap.ker (f ^ k.succ)
⊢ LinearMap.ker (f ^ (k + (finrank K V - k))) = LinearMap.ker (f ^ finrank K V)

Tactic:
rw [add_tsub_cancel_of_le h_k_le]

Goal state after:
Module: Mathlib.LinearAlgebra.Coevaluation

Goal state before:
pp: K : Type u
inst✝³ : Field K
V : Type v
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : FiniteDimensional K V
this : DecidableEq ↑(Basis.ofVectorSpaceIndex K V) := Classical.decEq ↑(Basis.ofVectorSpaceIndex K V)
j : ↑(Basis.ofVectorSpaceIndex K V)
⊢ (LinearMap.lTensor V (contractLeft K V))
      ((TensorProduct.assoc K V (Dual K V) V)
        ((LinearMap.rTensor V (coevaluation K V)) (1 ⊗ₜ[K] (Basis.ofVectorSpace K V) j))) =
    (TensorProduct.rid K V).symm ((Basis.ofVectorSpace K V) j)

Tactic:
rid_symm_apply

Goal state after:
K : Type u
inst✝³ : Field K
V : Type v
inst✝² : AddCommGroup V
inst✝¹ : Module K V
inst✝ : FiniteDimensional K V
this : DecidableEq ↑(Basis.ofVectorSpaceIndex K V) := Classical.decEq ↑(Basis.ofVectorSpaceIndex K V)
j : ↑(Basis.ofVectorSpaceIndex K V)
⊢ (LinearMap.lTensor V (contractLeft K V))
      ((TensorProduct.assoc K V (Dual K V) V)
        ((LinearMap.rTensor V (coevaluation K V)) (1 ⊗ₜ[K] (Basis.ofVectorSpace K V) j))) =
    (Basis.ofVectorSpace K V) j ⊗ₜ[K] 1