很多平面几何题的证明方法都不是唯一的．在平常的练习中有意识地进行一题多解，这对于沟通各部分数学知识的联系、拓宽自己的解题思路、提高分析问题和解决问题的能力，都是十分有益的．下面以一道题目的多种证法为例，说明平见证题的多向思维．例如图1，P为等边△ABC的外接圆 Many of the proof methods for plane geometry problems are not unique. In the usual practice, consciously carrying out a multi-solution, this is very useful for communicating the connection of various parts of mathematical knowledge, broadening their own problem-solving ideas, and improving the ability to analyze and solve problems. The following uses a variety of proofs of a topic as an example to illustrate the multi-directional thinking of the proofs. For example, in Fig. 1, P is the circumcircle of the equator △ ABC.