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公差不为零的等差数列{an}中,2a3-a72+2a11=0,数列{bn}是等比...
公差不为零的等差数列{an}中,2a3-a72+2a11=0,数列{bn}是等比数列,且b7=a7,则log2(b6b8)的值为 .
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