等比数列,an大于0.且a2a4+2a3a8a+a7a9=36,则a3+a8

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等比数列,an大于0.且a2a4+2a3a8a+a7a9=36,则a3+a8
等比数列,an大于0.且a2a4+2a3a8a+a7a9=36,则a3+a8

等比数列,an大于0.且a2a4+2a3a8a+a7a9=36,则a3+a8
a2a4=(a3)^2,a7a9=(a8)^2,所以原式=(a3+a8)^2=36,因为an>0,所以a3+a8=6