English
In a quiver with reverse, reversing a concatenation of paths satisfies: (p ⋅ q).reverse = q.reverse ⋅ p.reverse.
Русский
В кивере с обратным порядком стрелок выполнение: (p ⋅ q).reverse = q.reverse ⋅ p.reverse.
LaTeX
$$$ (p \\cdot q)^{\\mathrm{reverse}} = q^{\\mathrm{reverse}} \\cdot p^{\\mathrm{reverse}} $$$
Lean4
@[simp]
theorem reverse_comp [HasReverse V] {a b c : V} (p : Path a b) (q : Path b c) :
(p.comp q).reverse = q.reverse.comp p.reverse := by
induction q with
| nil => simp
| cons _ _ h => simp [h]