proposition: Lemma max_real : {in real &, forall x y, max x y \is real}.
proof: Proof. exact: comparable_maxr. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)