theorem Th58:
  for crq21, crq22 being State of CRtfsm2 holds crq21 = q1u &
  crq22 = q2u & tfsm = CRtfsm1-Mealy_union CRtfsm2 & not crq21, crq22
  -are_equivalent implies not q1u, q2u-are_equivalent
proof
  let crq21, crq22 be State of CRtfsm2;
  set rtfsm1 = CRtfsm1, rtfsm2 = CRtfsm2, q1 = crq21, q2 = crq22;
  assume that
A1: q1 = q1u and
A2: q2 = q2u and
A3: tfsm = rtfsm1-Mealy_union rtfsm2;
  assume not q1,q2-are_equivalent;
  then consider w be FinSequence of IAlph such that
A4: (q1,w)-response <> (q2,w)-response;
  (q1u,w)-response = (q1,w)-response by A1,A3,Th55;
  then (q1u,w)-response <> (q2u,w)-response by A2,A3,A4,Th55;
  hence thesis;
end;
