错位相减法是数列求和的常用方法.翻开每一年的数学高考试题,总有省或市的文科理科出现考查错位相减法的试题,重在考查数列的相关知识,考查运算能力、推理能力和综合分析和解决问题的能力.而能运用错位相减法计算出最终正确结果的考生少之又少.因此错位相减法之“错”在教与学中应给予重点关注. Mismatch subtraction method is a common method of sequence summation.Open the mathematics entrance exam questions every year, there are always provincial or city liberal arts science examinations appear dislocation subtraction method questions, focusing on examining the sequence of knowledge, to examine the computing power, reasoning Ability and the ability to analyze and solve the problem comprehensively, and the dislocation subtraction method to calculate the final correct results of the candidates is rare, so the dislocation subtraction method “wrong ” in teaching and learning should be given the key attention.