函数是中学数学的重要内容.它既是贯穿整个中学数学教学的一条主线,又是进一步学习高等数学所必备的基础知识,也是历年高考数学的重点考查内容.而抽象函数往往因无具体的解析表达式成为函数教学中的重点和难点内容,并使学生在解决有关问题时深感茫然和困难.本文针对具体问题,分情况给出求解策略. Function is an important content of middle school mathematics. It is not only a main thread throughout the middle school mathematics teaching, but also the basic knowledge necessary for further study of higher mathematics, and it is also a key examination content of the college entrance examination mathematics. The abstract function is often due to no specific analysis. The expression has become the key and difficult content in the function teaching, and makes the students feel profound and difficult when solving the related problems. This paper presents a solution strategy based on the specific problems.