proposition: Lemma le_exp mu f1 f2: \E?_[mu] f1 -> \E?_[mu] f2 -> f1 <=1 f2 -> \E_[mu] f1 <= \E_[mu] f2.
proof: Proof. move=> sm1 sm2 le_f; apply/le_sum => //. by move=> x; rewrite ler_wpM2r. Qed.
imports: mathcomp(all_ssreflect all_algebra) mathcomp.classical(boolp classical_sets mathcomp_extra) xfinmap ereal reals discrete topology realseq realsum