fact: Definition QmultS : QS --> QS --> QS.
imports: CoRN.algebra.RSetoid CoRN.model.metric2.Qmetric Coq.QArith.QArith CoRN.metric2.StepFunctionSetoid Coq.QArith.Qabs Coq.Bool.Bool CoRN.tactics.CornTac CoRN.logic.CornBasics CoRN.algebra.RSetoid