在正項(xiàng)等比數(shù)列
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中,
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,
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,則滿足
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的最大正整數(shù)
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的值為
.
試題分析:設(shè)正項(xiàng)等比數(shù)列
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首項(xiàng)為
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,公比為
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,
由題意可得
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解得,

,
故其通項(xiàng)公式為
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.
記
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,
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由
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,即
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化簡得,
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,因此只須
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即
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,
解得
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由于
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為正整數(shù),因此
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最大為
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的整數(shù)部分,也就是12.
故答案為12.
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
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
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
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
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
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
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
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
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
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
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
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
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