极限概念是描述数列和函数在无限过程中的变化趋势,引入的新符号较多,叙述方式又不同于学生以往学过的定义,有很高的科学的抽象性。极限定义联系到数列、函数、绝对值和不等式等方面的知识,从有限中认识无限,从近似中认识精确,从量变中认识质变,综合性很强。统编高中数学第四册在处理这部分重点教材上有几个突出的优点: The concept of limit is to describe the tendency of the series and function in the process of infinity. The introduction of new symbols is more, the way of narration is different from what the students have learned in the past and has a high degree of scientific abstraction. The definition of limit relates to the knowledge of series, function, absolute value and inequality. It knows infinite from the limit, recognizes the precise from the approximation, recognizes the qualitative change from the quantitative change, and is comprehensive. The compilation of high school mathematics fourth book in dealing with this part of the key textbook has several outstanding advantages: