幂函数是基本初等函数之一,是在学生系统学习了函数概念与函数性质之后,全面掌握有理数幂和根式的基础上来研究的一种特殊函数,是对函数概念及性质的应用. The power function is one of the basic elementary functions. It is a special function that is studied after the students have systematically studied the concept of functions and the nature of the functions, and has a complete mastery of the rational power and the root. It is the application of the concepts and properties of functions.