一、引言一天,有一位数学成绩较好的高三学生跑来问我:“老师,什么题型用倒序求和的方法?我好像一点概念都没有.”当时围在我身边的有同班的四、五位学生,我问他们能否举出一两个用倒序求和方法解决的简单例题,他们都表示好像有这种解题方法,但具体什么题型用,挺茫然的.针对此种情景,笔者在班上又做了一些访谈,发现几乎所有学生都没有把倒序求和作为求数列前n项和的重要思想方法,更不用谈什么时候使用此方法来解决何种类型数学 I. INTRODUCTION One day, a third year high school student with good math performance came to ask me: “Teacher, what type of question is summed in descending order? I do not seem to have any idea at all.” "There was a classmate around me Of the four or five students, I asked them if they could cite one or two simple examples that were solved by the method of reverse order summation, all of whom indicated that they seemed to have this method of solving problems, but what kind of questions they were using was quite dazed. In this scenario, I did some interviews in the class and found that almost all students did not use descending order sum as an important way to find the top n terms and sum, let alone when to use this method to solve what kind of math