fact: Definition expeR x := match x with | r%:E => (expR r)%:E | +oo => +oo | -oo => 0 end.
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