proposition: Lemma mulzK m d : d != 0 -> (m * d %/ d)%Z = m.
proof: Proof. by move=> d_nz; rewrite -[m * d]addr0 divzMDl // div0z addr0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop prime order) mathcomp(ssralg poly ssrnum ssrint archimedean rat matrix) mathcomp(polydiv perm zmodp mxalgebra vector)