12-13高二上·广东·期末
1 . 已知数列{an}中,
,设
.
(1)试写出数列{bn}的前三项;
(2)求证:数列{bn}是等比数列,并求数列{an}的通项公式an;
(3)设{an}的前n项和为Sn,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce53065131a665df8868b74e7a274705.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e43a949f999db0531883b3917504c4a7.png)
(1)试写出数列{bn}的前三项;
(2)求证:数列{bn}是等比数列,并求数列{an}的通项公式an;
(3)设{an}的前n项和为Sn,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ef0a0efa8339659d644e88f527c9fab.png)
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2 . 已知曲线
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28b26661c7e170b3da92eb42c84da457.png)
,从
上一点
作
轴的垂线,交
于点
,再从点
作
轴的垂线,交
于点
.设
,
,
(1)求
,
的坐标 ;
(2)求数列
的通项公式;
(3)记数列
的前
项和为
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f5c00a4cb3fc3783b4abeb06fb4d58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28b26661c7e170b3da92eb42c84da457.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/014f3f1128f7d6a93a4ea34967b96c88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/178f804adbf58b3b48ca1e6de3c2fba3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc31dcdb99754fc452ff2b92a2fb8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd9d64d968a4cb62d696c8ad1642eb23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87a60302649eb940748da818199e55da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c775fc62e7696028a9184e5212f0446.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0873d9cdecbadf963e9fedcd4edec86.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a86380a6d6501f6504dcb4aa5e3099f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eae863e7a1f1fed09f1075de4a817c63.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/153d172ee17295f0d6d60e891d3f6529.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cf4cea13f3c0a934a3be5a3d834774f.png)
![](https://img.xkw.com/dksih/QBM/2011/12/6/1570557903421440/1570557908967424/STEM/dca898e993214f328bf6c63826334f73.png?resizew=189)
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