分类讨论是一种重要的数学思想方法和解题策略,渗透到整个中学数学每个章节,由于这类题目综合性强,逻辑性严,探索性开放,自然也是难点.我们在重视分类讨论思想应用的基础上,也要注意克服动辄加以讨论的思维定势,要充分挖掘数学问题中潜在的特殊性,尽力打破常规,避免不必要的分 Category discussion is an important mathematical thinking and problem solving strategy, which infiltrates into every chapter of the whole middle school mathematics. Because such topics are comprehensive, logical and exploratory, naturally it is also a difficult point. Based on the application, but also pay attention to overcome the thinking to be easily discussed, to fully tap the potential of mathematical problems, try to break the routine, to avoid unnecessary points