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

theorem :: REAL_2'51
  (1 / a) * (1 / b) = 1 / (a * b)
proof
  thus (1/a)*(1/b)=a"*(1/b) by Lm4
    .=a"*b" by Lm4
    .=(a*b)" by Lm1
    .=1/(a*b) by Lm4;
end;
