proposition: Lemma expeR_inj : injective expeR.
proof: Proof. move=> [r| |] [s| |] => //=. - by move=> [] /expR_inj ->. - by case => /eqP; rewrite expR_eq0. - by case => /esym/eqP; rewrite expR_eq0. Qed.
imports: mathcomp(all_ssreflect ssralg ssrint ssrnum matrix) mathcomp(interval rat) mathcomp(boolp classical_sets functions) mathcomp(mathcomp_extra) reals ereal signed topology normedtype landau sequences derive realfun itv convex