函数与反函数是中学数学重要内容.这部分内容出现了对应、映射、一一映射、函数、逆映射等较为难懂的相关数学概念.这些概念之所以难理解,是因为它们在教材中的出现形式,并非都象其它重要定理、定义那样醒目和直白.教材体现侧重于知识的发生发展过程,更明确的概念、定义,要在教 Functions and inverse functions are the important contents of middle school mathematics. This part of the content shows the corresponding mathematical concepts such as correspondence, mapping, one-to-one mapping, functions, and inverse mapping. These concepts are difficult to understand because they are used in teaching materials. Appearance forms are not as striking and straightforward as other important theorems and definitions. Textbooks embody the process of knowledge development and development, and more explicit concepts and definitions must be taught.