已知數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117596455.png)
中,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117611416.png)
且
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117627634.png)
(
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117642421.png)
)。
(1)求
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117658333.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117674341.png)
的值;
(2)設(shè)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117689689.png)
,是否存在實(shí)數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117705288.png)
,使數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117720466.png)
為等差數(shù)列,若存在請(qǐng)求其通項(xiàng)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117736357.png)
,若不存在請(qǐng)說明理由。
(1)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117752480.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117783499.png)
(2)設(shè)存在實(shí)數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117705288.png)
,滿足題意,則
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117798610.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117830696.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117861734.png)
,且
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117876578.png)
即
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117892966.png)
解得
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117908470.png)
,此時(shí)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118001745.png)
又∵
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232041182041808.png)
∴
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118220479.png)
是以1為公差,首項(xiàng)為
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118251779.png)
的等差數(shù)列
∴
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118266625.png)
,故存在實(shí)數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204117908470.png)
,使數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118220479.png)
為等差數(shù)列,且
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204118266625.png)
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已知數(shù)列{a
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n=
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823232142064617.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823232142204297.png)
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設(shè)數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624332415.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624363365.png)
,
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624425324.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624441323.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624456659.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624472440.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624519767.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823205624534874.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204333363172.png)
1)小問6分,(2)小分6分.)
已知函數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204333378753.png)
,數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204333425460.png)
滿足
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,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204333472519.png)
.
(1)求證:
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823204333503718.png)
;
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232043335191846.png)
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科目:高中數(shù)學(xué)
來源:不詳
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(本小題滿分14分)
已知數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203757806465.png)
滿足:
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203757837485.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758009992.png)
(其中
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758056253.png)
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(1)求數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203757806465.png)
的通項(xiàng)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758227372.png)
;
(2)設(shè)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758415730.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758430735.png)
,求證:
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758446642.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203758477532.png)
.
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科目:高中數(shù)學(xué)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509825481.png)
的前
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509841297.png)
項(xiàng)和為
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,對(duì)任意的正整數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509841297.png)
,都有
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成立,記
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232035101211039.png)
?
(I)求數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510199491.png)
的通項(xiàng)公式;
(II)記
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510215938.png)
,設(shè)數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510231450.png)
的前
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509841297.png)
項(xiàng)和為
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510277373.png)
,求證:對(duì)任意正整數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509841297.png)
都有
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510324574.png)
;
(III)設(shè)數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510199491.png)
的前
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203509841297.png)
項(xiàng)和為
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510433366.png)
?已知正實(shí)數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510449323.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510480646.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823203510449323.png)
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(本小題滿分13分)
已知數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341021457.png)
是等比數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341037656.png)
數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341053476.png)
是等差數(shù)列,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341068451.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341084945.png)
(Ⅰ)求數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341053476.png)
的通項(xiàng)公式;
(Ⅱ)求數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341053476.png)
的前
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341131297.png)
項(xiàng)和
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341162388.png)
;
(Ⅲ)設(shè)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341177878.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341209935.png)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341224610.png)
比較
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341240358.png)
與
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823202341255395.png)
大小,并證明你的結(jié)論。
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科目:高中數(shù)學(xué)
來源:不詳
題型:解答題
(理)正數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313611471.png)
的前
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313627297.png)
項(xiàng)和
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313658388.png)
滿足:
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313767661.png)
,
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313814499.png)
常數(shù)
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313830461.png)
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313845489.png)
是一個(gè)定值;
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313611471.png)
是一個(gè)周期數(shù)列,求該數(shù)列的周期;
(3)若數(shù)列
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313611471.png)
是一個(gè)有理數(shù)等差數(shù)列,求
![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/20140823200313658388.png)
.
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來源:不詳
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![](http://thumb.zyjl.cn/pic2/upload/papers/20140823/201408232047222781127.png)
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