Theorem: CategoryTheory.Localization.Preadditive.add'_zero
File: Mathlib/CategoryTheory/Localization/CalculusOfFractions/Preadditive.lean

Proof steps:
state_before: C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
⊢ add' W f (L.map 0) = f
state_after: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ add' W f (L.map 0) = f
tactic: obtain ⟨α, hα⟩ := exists_leftFraction L W f
state_before: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ add' W f (L.map 0) = f
state_after: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction₂.mk α.f 0 α.s ⋯).add.map L ⋯ = α.map L ⋯

case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ L.map 0 = (LeftFraction₂.mk α.f 0 α.s ⋯).snd.map L ⋯
tactic: rw [add'_eq W f (L.map 0) (LeftFraction₂.mk α.f 0 α.s α.hs) hα, hα]
state_before: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction₂.mk α.f 0 α.s ⋯).add.map L ⋯ = α.map L ⋯

case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ L.map 0 = (LeftFraction₂.mk α.f 0 α.s ⋯).snd.map L ⋯
state_after: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ L.map 0 = (LeftFraction₂.mk α.f 0 α.s ⋯).snd.map L ⋯

case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction₂.mk α.f 0 α.s ⋯).add.map L ⋯ = α.map L ⋯
tactic: swap
state_before: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction₂.mk α.f 0 α.s ⋯).add.map L ⋯ = α.map L ⋯
state_after: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction.mk (α.f + 0) α.s ⋯).map L ⋯ = α.map L ⋯
tactic: dsimp [LeftFraction₂.add]
state_before: case intro
C : Type u_1
D : Type u_2
inst✝⁴ : Category.{u_4, u_1} C
inst✝³ : Category.{u_3, u_2} D
inst✝² : Preadditive C
L : C ⥤ D
W : MorphismProperty C
inst✝¹ : L.IsLocalization W
inst✝ : W.HasLeftCalculusOfFractions
X Y Z : C
f : L.obj X ⟶ L.obj Y
α : W.LeftFraction X Y
hα : f = α.map L ⋯
⊢ (LeftFraction.mk (α.f + 0) α.s ⋯).map L ⋯ = α.map L ⋯
state_after: no goals
tactic: rw [add_zero]