已知等比数列{an}满足an>0,n=1,2,3…,且a5?a6=8,则log2a2+log2a3+log2a4+log2a5+log2a6+log2a7+log2a8+log2a9=A.4B.5C.6D.12
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D
解析分析:由等比数列的定义和性质可得a2a9=a3a8=a4a7=a5a6=8,要求的式子即log2(a2a9?a3a8?a4a7?a5a6),即,再利用对数的运算性质求出结果.
解答:由等比数列{an}满足an>0,n=1,2,3…,且a5?a6=8,可得a2a9=a3a8=a4a7=a5a6=8.∴log2a2+log2a3+log2a4+log2a5+log2a6+log2a7+log2a8+log2a9 =log2(a2a9?a3a8?a4a7?a5a6)===12,故选D.
点评:本题主要考查等比数列的定义和性质,对数的运算性质的应用,属于中档题.