4,a1,a2是等比数列a2,a3,64是等比数列a1^2=4*a2>0所以a2>0a3^2=64a2a1^2=4a2等差，所以2a2=a1+a3a3^2=64a2a1^2=4a2若a3=8√a2,a1=2√a2则2a2=10√a2a2=25,a3=40,a1=10若a3=-8√a2,a1=2√a2则2a2=-6√a2,不符合a2>0若a3=8√a2,a1=-2√a2则2a2=6√a2a2=9,a3=24,a1=-6若a3=-8√a2,a1=-2√a2则2a2=-10√a2,不符合a2>0所以a2=25,a3=40,a1=10a2=9,a3=24,a...
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