求二次函数的最值是同学们普遍感到困难的题型,特别是对于含参变量的最值问题,感觉更是难以驾驭.本文给出一种简便方法——特殊点验证法,即首先由特殊点的最值,求得参变量,再验证其真伪,从而回避复杂讨论,使解题收到事半功倍之效.现分类举例说明如下,供同学们学习时参考. Finding the maximum value of the quadratic function is a type of problem that students generally find difficult. Especially for the problem of the value of the parametric variable, the feeling is even more difficult to control. This article gives a simple method - special point verification method, that is, first From the most value of the special point, to obtain the parameter, and then verify the authenticity, so as to avoid the complex discussion, so that the problem has been more effective. The classification is illustrated as follows, for reference when students learn.