proposition: Lemma opp_creal0 : - 0 == 0.
proof: Proof. by apply: eq_crealP; exists m0=> * /=; rewrite oppr0 addr0 normr0. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(bigop order ssralg ssrnum ssrint rat poly polydiv polyorder) mathcomp(perm matrix mxpoly polyXY binomial bigenough)