設(shè)S
k=
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+
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+
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+…+
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,則S
k+1為( )
A.S
k+

B.S
k+
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+
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C.S
k+
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-
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D.S
k+
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-
【答案】
分析:先利用S
k=
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+
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+
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+…+
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,表示出S
k+1,再進行整理即可得到結(jié)論.
解答:解:因為S
k=
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+
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+
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+…+

,
所以s
k+1=
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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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=s
k
-
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.
故選 C.
點評:本題主要考查數(shù)列遞推關(guān)系式,屬于易錯題,易錯點在與整理過程中,不能清楚哪些項有,哪些項沒有.
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