proposition: Lemma add_mpoly0 : left_id 0%:MP mpoly_add.
proof: Proof. by move=> p; apply/mpoly_eqP; rewrite !mpoly_valK freegU0 add0r. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype tuple finfun bigop finset binomial) mathcomp(order fingroup perm ssralg zmodp poly ssrint) mathcomp(matrix vector) mathcomp(bigenough) ssrcomplements freeg