proposition: Lemma expeR_eq0 x : (expeR x == 0) = (x == -oo).
proof: Proof. by case: x => //= [r|]; rewrite ?eqxx// eqe 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