Module: Mathlib.CategoryTheory.GradedObject.Monoidal

Goal state before:
pp: I : Type u
inst✝²⁵ : AddMonoid I
C : Type u_1
inst✝²⁴ : Category.{v_1, u_1} C
inst✝²³ : MonoidalCategory C
X₁ X₂ X₃ X₄ : GradedObject I C
inst✝²² : X₁.HasTensor X₂
inst✝²¹ : X₂.HasTensor X₃
inst✝²⁰ : X₃.HasTensor X₄
inst✝¹⁹ : (tensorObj X₁ X₂).HasTensor X₃
inst✝¹⁸ : X₁.HasTensor (tensorObj X₂ X₃)
inst✝¹⁷ : (tensorObj X₂ X₃).HasTensor X₄
inst✝¹⁶ : X₂.HasTensor (tensorObj X₃ X₄)
inst✝¹⁵ : (tensorObj (tensorObj X₁ X₂) X₃).HasTensor X₄
inst✝¹⁴ : (tensorObj X₁ (tensorObj X₂ X₃)).HasTensor X₄
inst✝¹³ : X₁.HasTensor (tensorObj (tensorObj X₂ X₃) X₄)
inst✝¹² : X₁.HasTensor (tensorObj X₂ (tensorObj X₃ X₄))
inst✝¹¹ : (tensorObj X₁ X₂).HasTensor (tensorObj X₃ X₄)
inst✝¹⁰ : X₁.HasGoodTensor₁₂Tensor X₂ X₃
inst✝⁹ : X₁.HasGoodTensorTensor₂₃ X₂ X₃
inst✝⁸ : X₁.HasGoodTensor₁₂Tensor (tensorObj X₂ X₃) X₄
inst✝⁷ : X₁.HasGoodTensorTensor₂₃ (tensorObj X₂ X₃) X₄
inst✝⁶ : X₂.HasGoodTensor₁₂Tensor X₃ X₄
inst✝⁵ : X₂.HasGoodTensorTensor₂₃ X₃ X₄
inst✝⁴ : (tensorObj X₁ X₂).HasGoodTensor₁₂Tensor X₃ X₄
inst✝³ : (tensorObj X₁ X₂).HasGoodTensorTensor₂₃ X₃ X₄
inst✝² : X₁.HasGoodTensor₁₂Tensor X₂ (tensorObj X₃ X₄)
inst✝¹ : X₁.HasGoodTensorTensor₂₃ X₂ (tensorObj X₃ X₄)
inst✝ : X₁.HasTensor₄ObjExt X₂ X₃ X₄
j i₁ i₂ i₃ i₄ : I
h : i₁ + i₂ + i₃ + i₄ = j
| X₁ i₁ ◁ ιTensorObj₃ X₂ X₃ X₄ i₂ i₃ i₄ (i₂ + i₃ + i₄) ⋯ ≫
    (𝟙 (X₁ i₁) ⊗ₘ (associator X₂ X₃ X₄).inv (i₂ + i₃ + i₄)) ≫
      ιTensorObj X₁ (tensorObj (tensorObj X₂ X₃) X₄) i₁ (i₂ + i₃ + i₄) j ⋯ ≫
        (associator X₁ (tensorObj X₂ X₃) X₄).inv j ≫ tensorHom (associator X₁ X₂ X₃).inv (𝟙 X₄) j

Tactic:
rw [id_tensorHom, ← MonoidalCategory.whiskerLeft_comp_assoc, ιTensorObj₃_associator_inv,
      ιTensorObj₃'_eq X₂ X₃ X₄ i₂ i₃ i₄ _ rfl _ rfl, MonoidalCategory.whiskerLeft_comp_assoc,
      MonoidalCategory.whiskerLeft_comp_assoc,
      ← ιTensorObj₃_eq_assoc X₁ (tensorObj X₂ X₃) X₄ i₁ (i₂ + i₃) i₄ j
        (by simp only [← add_assoc, h]) _ rfl, ιTensorObj₃_associator_inv_assoc,
      ιTensorObj₃'_eq_assoc X₁ (tensorObj X₂ X₃) X₄ i₁ (i₂ + i₃) i₄ j
        (by simp only [← add_assoc, h]) (i₁ + i₂ + i₃) (by rw [add_assoc]), ι_tensorHom]

Goal state after:
I : Type u
inst✝²⁵ : AddMonoid I
C : Type u_1
inst✝²⁴ : Category.{v_1, u_1} C
inst✝²³ : MonoidalCategory C
X₁ X₂ X₃ X₄ : GradedObject I C
inst✝²² : X₁.HasTensor X₂
inst✝²¹ : X₂.HasTensor X₃
inst✝²⁰ : X₃.HasTensor X₄
inst✝¹⁹ : (tensorObj X₁ X₂).HasTensor X₃
inst✝¹⁸ : X₁.HasTensor (tensorObj X₂ X₃)
inst✝¹⁷ : (tensorObj X₂ X₃).HasTensor X₄
inst✝¹⁶ : X₂.HasTensor (tensorObj X₃ X₄)
inst✝¹⁵ : (tensorObj (tensorObj X₁ X₂) X₃).HasTensor X₄
inst✝¹⁴ : (tensorObj X₁ (tensorObj X₂ X₃)).HasTensor X₄
inst✝¹³ : X₁.HasTensor (tensorObj (tensorObj X₂ X₃) X₄)
inst✝¹² : X₁.HasTensor (tensorObj X₂ (tensorObj X₃ X₄))
inst✝¹¹ : (tensorObj X₁ X₂).HasTensor (tensorObj X₃ X₄)
inst✝¹⁰ : X₁.HasGoodTensor₁₂Tensor X₂ X₃
inst✝⁹ : X₁.HasGoodTensorTensor₂₃ X₂ X₃
inst✝⁸ : X₁.HasGoodTensor₁₂Tensor (tensorObj X₂ X₃) X₄
inst✝⁷ : X₁.HasGoodTensorTensor₂₃ (tensorObj X₂ X₃) X₄
inst✝⁶ : X₂.HasGoodTensor₁₂Tensor X₃ X₄
inst✝⁵ : X₂.HasGoodTensorTensor₂₃ X₃ X₄
inst✝⁴ : (tensorObj X₁ X₂).HasGoodTensor₁₂Tensor X₃ X₄
inst✝³ : (tensorObj X₁ X₂).HasGoodTensorTensor₂₃ X₃ X₄
inst✝² : X₁.HasGoodTensor₁₂Tensor X₂ (tensorObj X₃ X₄)
inst✝¹ : X₁.HasGoodTensorTensor₂₃ X₂ (tensorObj X₃ X₄)
inst✝ : X₁.HasTensor₄ObjExt X₂ X₃ X₄
j i₁ i₂ i₃ i₄ : I
h : i₁ + i₂ + i₃ + i₄ = j
| X₁ i₁ ◁ (α_ (X₂ i₂) (X₃ i₃) (X₄ i₄)).inv ≫
    X₁ i₁ ◁ ιTensorObj X₂ X₃ i₂ i₃ (i₂ + i₃) ⋯ ▷ X₄ i₄ ≫
      (α_ (X₁ i₁) (tensorObj X₂ X₃ (i₂ + i₃)) (X₄ i₄)).inv ≫
        ιTensorObj X₁ (tensorObj X₂ X₃) i₁ (i₂ + i₃) (i₁ + i₂ + i₃) ⋯ ▷ X₄ i₄ ≫
          ((associator X₁ X₂ X₃).inv (i₁ + i₂ + i₃) ⊗ₘ 𝟙 X₄ i₄) ≫
            ιTensorObj (tensorObj (tensorObj X₁ X₂) X₃) X₄ (i₁ + i₂ + i₃) i₄ j ⋯