proposition: Lemma pos_split_deg p: p != 0 -> size p = ((npos_roots p) + (size (pos_cofactor p))) %N.
proof: Proof. move /pos_split1 => [[pa _ _ ] _ _ pb]. by rewrite {1} pa size_monicM // ? monic_prod_XsubCe // size_prod_XsubCe addSn. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice fintype order) mathcomp(binomial bigop ssralg poly ssrnum ssrint rat) mathcomp(polydiv polyorder path interval polyrcf)