已知等比數(shù)列{a
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}的公比為正數(shù),且a
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·a
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=2a

,a

=1,則a
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=
試題分析:因為,等比數(shù)列{a
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}的公比為正數(shù),且a

·a

=2a

,
所以,由等比數(shù)列的性質(zhì),得,
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,公比為
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,
又a
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=1,所以,a
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=
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,選B。
點評:簡單題,在等比數(shù)列中,如果,
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,那么,
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。
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