proposition: Lemma intRM m1 m2 : (m1 * m2)%R == m1 * m2.
proof: Proof. suffices intMn m n: (m * n)%R == m * n. by case: m2 => n; rewrite ?NegzE ?mulrN ?intRN ?mulRN intMn. rewrite -mulrzz -pmulrn; elim: n => [|n IHn]; first by rewrite mulR0. by rewrite mulrS (PoszD 1%N) !intRD mulRDr mulR1 -IHn. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div order) mathcomp(ssralg ssrnum ssrint rat intdiv) Coq(Morphisms Setoid) fourcolor(real realsyntax)