proposition: Lemma ler1_real x : x <= 1 -> x \is real.
proof: Proof. by move=> /ler_real->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)