reserve a, b, c, d, e for Complex;

theorem :: REAL_2'55
  c <> 0 implies a / b = a / c * (c / b)
proof
  assume
A1: c<>0;
  thus a/b=a*b" by XCMPLX_0:def 9
    .=a/c*c*b" by A1,Lm3
    .=a/c*(c*b")
    .=a/c*(c/b) by XCMPLX_0:def 9;
end;
