不等式是中学数学的重要内容 ,与各部分都有着密切的联系 .是历年高考的命题重点 .在考察不等式的试题中以含字母参数的居多 ,解决此类问题的方法突出体现了等价转化、函数与方程、分类讨论、数形结合等数学思想 .1　合理分类 ,逐类求解研究含字母参数的不等式 ,大多数情况下要 Inequality is an important content of middle school mathematics, and it has close connection with all parts. It is the proposition focus of the college entrance examination over the years. In examining inequalities in the test questions, most of them include alphabetic parameters. The method of solving such problems highlights the equivalent transformation, Mathematical ideas such as functions and equations, classification discussion, and combination of number and shape.1 Reasonable classification, class-by-class solving for inequalities with letter parameters, in most cases