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已知{an}是各项均为正数的等比数列,a1a2a3=5,a7a8a9=10,则a...
已知{an}是各项均为正数的等比数列,a1a2a3=5,a7a8a9=10,则a4a5a6= .
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C.1
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|=1,|
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,
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•
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