proposition: Lemma divmxK m n l (M : 'M[R]_(m, n)) (B : 'M_(l, n)) : M %| B -> divmx B M *m M = B.
proof: Proof. by move/eqP. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg fintype perm choice matrix bigop zmodp mxalgebra poly) ssrcomplements dvdring stronglydiscrete