题目描述：
在等比数列{an}中,a3=1/2,a7=1/32,求a5答案解析
【答案】q>0时,由已知a3>0 a7>0知数列各项均为正,a5>0q0 a3>0 a5>0
综上,得a5>0
a3a7=a1²q^8=(a1q⁴)²=a5²=(1/2)(1/32)=1/64
a5=1/8或a5=-1/8( 【其他答案】a7
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