proposition: Lemma qpoly_mul_addl : left_distributive (@qpoly_mul A h) +%R.
proof: Proof. by move=> p q r; rewrite -!(qpoly_mulC r) qpoly_mul_addr. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice fintype tuple) mathcomp(bigop binomial finset finfun ssralg countalg finalg poly polydiv) mathcomp(perm fingroup matrix mxalgebra mxpoly vector countalg)