reserve a,b,c,d for Real;
reserve z,z1,z2 for Complex;

theorem
  (z1/z2)*' = (z1*')/(z2*')
proof
  thus (z1/z2)*' = (z1*z2")*' by XCMPLX_0:def 9
    .= (z1*'*z2"*') by Th35
    .= (z1*'*z2*'") by Th36
    .= (z1*')/(z2*') by XCMPLX_0:def 9;
end;
