proposition: Lemma trmx_inv (A : 'M_n) : (invmx A)^T = invmx (A^T).
proof: Proof. by rewrite (fun_if trmx) linearZ /= trmx_adj -unitmx_tr -det_tr. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg countalg finalg zmodp)