proposition: Lemma deg2_poly_ge0l x : x <= r1 -> 0 <= p.[x].
proof: Proof. by move=> ?; apply: deg2_poly_ge0l; rewrite // -/a ?a1 ?ler01 ?mulr1. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)