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问题: 一道数学数列题,求详解

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解答:

a2 =a1 +1/4 =a +1/4
a3 =a2/2 =a/2 +1/8
a(2n+1) =(a2n)/2 =[a(2n-1) +1/4]/2 =a(2n-1)/2 +1/8
==> a(2n+1) -1/4 =[a(2n-1) -1/4]/2
==> b(n+1) =bn/2, b1 =a -1/4 不等于零0
==> {bn}为等比数列, 公比 =1/2, 首项 =a -1/4