文[1]介绍了用(-1)n求摆动数列的通项,本文介绍另一种方法,即通过“替换─消项”构造公比为-1的等比数列巧求摆动数列的通项.此法简便,易于操作.例1已知数列{an}中,an+1+an=5,a1=2,求数列{an}的通项公式.解作替换an=bn+μ,由an+1+an=5,得(bn+1+μ)+(bn+μ)=5,即bn+1=-bn+5-2μ, The paper [1] introduced the general term of (1)n to find the series of the wobbles. This paper introduces another method, that is, through the “replacement-elimination term” to construct the analogy of the common ratio of -1 to the number of the sequence of the number of the wobble sequence. Item. This method is simple and easy to operate. Example 1 In the known sequence {an}, an+1+an=5, a1=2, find the general term formula of the sequence {an}, and replace it with an=bn+μ. From an+1+an=5, we get (bn+1+μ)+(bn+μ)=5, that is bn+1=-bn+5-2μ,