波利亚指出 :“如果你不能解决所提的问题 ,可尝试先去解决某个与此有关的辅助问题 ,一个更易着手的特殊问题 ,这正像小河当中正好有块合适的石头可作为临时的踏脚石 ,我们用两步过河一样 .”转移法求轨迹方程的根本策略就是寻找踏脚石 ,两步实现目的 .平时我们所熟悉的 ,在其 Polya pointed out: “If you can’t solve the problem you mentioned, try to solve some auxiliary problem related to it, a special problem that is easier to start. This is just like there is a suitable stone in the river that can be used as temporary. Stepping stone, we use the same two-step river.” Fundamental strategy of the transfer method to find the trajectory equation is to find a stepping stone, two steps to achieve the purpose. Usually we are familiar with, in its