proposition: Lemma expRB x y : expR (x - y) = expR x / expR y.
proof: Proof. by rewrite expRD expRN. 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