reserve z,z1,z2,z3,z4 for Element of F_Complex;

theorem
  z <> 0.F_Complex implies z"*' = z*'"
proof
  reconsider z1=z as Element of COMPLEX by Def1;
  assume
A1: z <> 0.F_Complex;
  then
A2: z*' <> 0.F_Complex by Th48;
  z" = z1" by A1,Th5;
  hence z"*' = z1*'" by COMPLEX1:36
    .= z*'" by A2,Th5;
end;
