一道数学数列题,a_(n+1)=1/[3^(n+1)]
、因为a_(n+1)=1/[3^(n+1)]
所以an=1/(3^n).
人气:465 ℃ 时间:2020-05-10 05:45:07
解答
令k=n+1,则由 a_(n+1)=1/[3^(n+1)]有
a_k =1/(3^k)
再把k换成n有
a_n=1/(3^n).
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