Rational number can approximate to real number,use the notation of Approximate one can prove Riemann function isn t differentiable anywhere,that the Rational points are dense in unit circle.

• 利用有理数对实数逼近的表示方式,给出黎曼函数处处不可导的一种证明,给出单位圆周上的有理点在单位圆上稠密的证明。