分段函数是中学数学中一种常见的函数,在日常生活中也普遍存在,具有广泛的应用.由于现行教材对分段函数只是以例题形式出现,而未作系统的介绍,教学中,发现不少学生总觉得分段函数的问题难于理解,解题时频频出错,究其原因,一是由于学生的认知结构仍然停留在初中阶段所学的一次函数、二次函数和反比例函数的情景上,对分段函数缺乏深刻的认识;二是教师在教学中没有予以足够的重视,未能有计划地对分段函数的有关知识进行渗透、补充和归纳,使之系统化.本文将笔者在进行分段函数教学中的几点体会笔录如下,供大家参考. Segment function is a common function in middle school mathematics. It is also widely used in daily life. It has a wide range of applications. Because the current textbooks only appear in the form of example questions for segment functions, they are not introduced systematically. Many students always feel that the problem of piecewise function is difficult to understand, and that the problem is frequently made when the problem is solved. The first reason is that the cognitive structure of students still stays in the scene of a function, a quadratic function and an inversely proportional function learned in junior high school. On the other hand, there is a lack of understanding of the segmentation function. Second, teachers do not pay enough attention to the teaching. They fail to systematically infiltrate, supplement, and generalize the knowledge of the segmented function and make it systematic. A few points of experience in the function of segment function teaching are as follows, for your reference.