proposition: Lemma deg2_poly_ge0m x : 0 <= delta -> r1 <= x <= r2 -> 0 <= p.[x].
proof: Proof. by move=> ? ?; rewrite -oppr_le0 -hornerN deg2_poly_le0m ?deltaN// r1N r2N. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)