求动点的轨迹问题

Solution to the locus equation of moving point

根据动点所满足的几何条件或数量关系求动点的轨迹(方程)问题的基本方法有五种:直接法;定义法;代入法;参数法;交轨法。这些方法都有其特定性和局限性,各种方法之间又是相互联系的,相互渗透的,我们在求轨迹方程时,所选取的出发点不同,方法可能就不同。

This paper discusses five methods of solving the locus equation of moving points which accord with geometric condition or quantitative relation. The five methods are direct method,definition method, substitution method,parameter method and trajectory method. These methods have their own property and limitation,but they are connected with and penetrated each other. When a locus equation needs to be solved, different methods can be chosen according to different conditions.