proposition: Lemma exprn_ile1 n x : 0 <= x -> x <= 1 -> x ^+ n <= 1.
proof: Proof. move=> xge0 xle1; elim: n=> [|*]; rewrite ?expr0 // exprS. by rewrite mulr_ile1 ?exprn_ge0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)