proposition: Lemma submxrowB m (B B' : 'M[V]_(m, sq)) j : submxrow (B - B') j = submxrow B j - submxrow B' j.
proof: Proof. by apply/matrixP => i i'; rewrite !mxE. 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)