proposition: Lemma modp_mul p q m : (p * (q %% m)) %% m = (p * q) %% m.
proof: Proof. by rewrite [in RHS](divp_eq q m) mulrDr modpD mulrA modp_mull add0r. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop ssralg poly)