公差不為零的等差數(shù)列第2,3,6項構(gòu)成等比數(shù)列,則這三項的公比為( )
試題分析:等差數(shù)列第2,3,6項分別為
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,由
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,得d=2
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,這三項的公比為3,故選C。
點評:簡單題,依據(jù)已知條件建立首項、公差的關(guān)系式,進一步確定公比。
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