已知等差数列{an}中,an=2n-24 若数列{bn}满足an=log2bn,设Tn=b1b2...bn,且Tn=1,求n的值
人气:380 ℃ 时间:2020-05-26 17:55:36
解答
由 an=log2bn 得: bn=2^(an)所以 Tn = b1*b2*b3……bn= 2^a1*2^a2*2^a3*……*2^an= 2^(a1+a2+a3+……+an) 在这里我们就设:Sn=a1+a2+a3+……+an Tn=2^Sn ...
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