已知数列
满足
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afa5700d9cdf20dd4bd05bf597229065.png)
(1)记
,求证:
为等比数列;
(2)若
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afa5700d9cdf20dd4bd05bf597229065.png)
(1)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89f2cd7832afe02641ca767c8f0b45a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fde513254e2cff153fdc6306ebc1c4ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b9a0d7150fb24be3e28ef7f0e18be93.png)
更新时间:2023-07-27 21:49:21
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相似题推荐
解答题-问答题
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适中
(0.65)
名校
【推荐1】已知数列
的前
项和
,其中
.
(Ⅰ)求数列
的通项公式;
(Ⅱ)若
(
)为等比数列
的前三项,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/201c985aeb7a5c440bee38f1f8b8e460.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
(Ⅰ)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/335112fe8b0738341b7622375af07415.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46b6d151d3f864bae873987f6db9327a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
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【推荐2】2023年10月26日,神舟十七号顺利发射,我国史上最年轻航天员乘组创造了中国航天历史.这一伟大壮举激发了行知中学学生学习航天知识的热情,学校开展了“航天知识竞赛”活动.活动分为三个阶段,第一阶段为“初赛”,通过网络答题活动,遴选优秀学生60名;第二阶段为“复赛”,由初赛遴选的60名学生进行“航天模型设计”竞赛;第三阶段为“决赛”,由“复赛”成绩前2名的学生进行“空间知识竞赛”决赛,获胜者授予“航天小达人”称号.现统计参加“航天模型设计”竞赛的60名学生的成绩得到频率分布直方图如下:
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/17/a13ca926-5376-4482-8711-5130214023db.png?resizew=263)
(1)根据频率分布直方图,估计参加“航天模型设计”竞赛的60名学生的成绩平均分;
(2)已知甲、乙两名同学参加决赛,决赛采取现场答题的方式进行.比赛规则如下:若选手答对题,则继续下一次答题;若答错题,则由另一位选手进行下一次答题.已知甲、乙两位选手答对任一试题的概率均为
,每次答题相互独立,且甲选手答第1题.
①求前3次答题,甲答2次题的概率;
②设第
次为甲答题的概率为
,求
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/17/a13ca926-5376-4482-8711-5130214023db.png?resizew=263)
(1)根据频率分布直方图,估计参加“航天模型设计”竞赛的60名学生的成绩平均分;
(2)已知甲、乙两名同学参加决赛,决赛采取现场答题的方式进行.比赛规则如下:若选手答对题,则继续下一次答题;若答错题,则由另一位选手进行下一次答题.已知甲、乙两位选手答对任一试题的概率均为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
①求前3次答题,甲答2次题的概率;
②设第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
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解题方法
【推荐1】已知成等差数列的三个正数的和等于15,并且这三个数分别加上2,5,13后成为等比数列
中的
,
,
.若数列
的前
项和为
,求数列
的前
项和.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57483e04fd1840c87ac5325157149877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a548938d87c80ac47910607d3857007f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f6714682274c31a328bf796e235900.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.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/387ad3d2b81583c9e051a4dfbf9eb1b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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【推荐2】已知等差数列
满足
,
,数列
的前n项和为
,且
.
(1)求数列
,
的通项公式;
(2)求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ba9cb8808927a2d4c3055850a32d11c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/292acb9c72abdbb2a8704e1c438bf27e.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec4bdc2a6d4fc387dc621f0b5a268c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
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(0.65)
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解题方法
【推荐1】已知数列
是正项等比数列,其前n项和为
,且
,
.
(1)求
的通项公式;
(2)记
的前n项和为
,求满足
的最大整数n.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/105fd92af4a217572cc971e485b450c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bea56bcdb039347b2e436d9446dc7ee1.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41d22c520a6f264eff601fd3c0a5863e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d48159ca3c314bbb3b2a1f20b29feb68.png)
您最近一年使用:0次
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适中
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名校
解题方法
【推荐2】已知数列
是等差数列,
,
.
(1)求数列
的通项公式;
(2)若
,求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b13a6e1d671215fc96e4bee3541d1096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6278d3cc0086c7aab6ac20712c7d0bd.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/449f35002286a48a6524466e671d9314.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次