设等比数列{an}的前n项和为Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,则a10等于 ____.
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![设等比数列{an}的前n项和为Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,则a10等于 ____.](/uploads/image/z/11626000-16-0.jpg?t=%E8%AE%BE%E7%AD%89%E6%AF%94%E6%95%B0%E5%88%97%7Ban%7D%E7%9A%84%E5%89%8Dn%E9%A1%B9%E5%92%8C%E4%B8%BASn%2C%E8%8B%A5S2n%3D3%28a1%2Ba3%2B%E2%80%A6%2Ba2n%EF%BC%8D1%29%2Ca1a2a3%3D8%2C%E5%88%99a10%E7%AD%89%E4%BA%8E+____.)
设等比数列{an}的前n项和为Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,则a10等于 ____.
设等比数列{an}的前n项和为Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,则a10等于 ____.
设等比数列{an}的前n项和为Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,则a10等于 ____.
a1+a3+…+a2n-1+a2+a4+…+a2n=3(a1+a3+…+a2n-1)
a2+a4+…+a2n=q(a1+a3+…+a2n-1)=2(a1+a3+…+a2n-1)
q=2
8a1=8
a1=1
a10=512