对于高考试题中出现的求形如{an·bn}(其中{an}是公差为d(d≠0)的等差数列,{bn}是公比为q(q≠1)的等比数列)的前n项和Sn问题,命题组给出的标准答案历来都是采用“错位相减法”.然而,我们发现学生不仅感觉到厌烦,而且计算量大、错误率高.那么是否有其他的方法可以替代“错位相减法”来求这类数列的和,从而减少计算量和错误 For the appearance of the college entrance examination test such as {an · bn} (where {an} is an arithmetic sequence with a tolerance of d (d ≠ 0), {bn} is a geometric sequence with an equal to q (q ≠ 1) ), The standard answer given by the proposition group always adopts “Displacement Subtraction Method.” However, we find that students not only feel boring but also have a large amount of calculation and a high error rate, Other methods can be used instead of the “Displacement Subtraction Method” to find the sum of such sequences, thereby reducing the amount of computation and errors