初中数学中有一类动态问题中探求定值的问题,时常在中考中出现.此类问题探索性强,涉及的知识面广,解题方法灵活,因而难度较大,对学生的要求比较高,常常令部分学生束手无策.实际上,解决这类问题的基本思 There are one type of dynamic problems in junior high school mathematics, which often appear in the middle school exam. Such problems are highly exploratory, involve a wide range of knowledge, and are flexible in solving problems. Therefore, they are more difficult and have higher requirements for students. Often some students are helpless. In fact, the basic thinking to solve such problems