1 . 在一个有穷数列的每相邻两项之间插入这两项的和,形成新的数列,我们把这样的操作称为该数列的一次“和扩充”.如数列1,2第1次“和扩充”后得到数列1,3,2,第2次“和扩充”后得到数列1,4,3,5,2.设数列a,b,c经过第n次“和扩充”后所得数列的项数记为
,所有项的和记为
.
(1)求
;
(2)若
,求n的最小值;
(3)是否存在实数
,使得数列
为等比数列?若存在,求出
满足的条件;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5425108c557f0f21474c045334f97d9c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dcd08431daac10be93e6fafbc5d4a90.png)
(3)是否存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce224c28ca451c4f105dc3b077736cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
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2 . 已知公差不为0的等差数列
,前n项和为
,且
,_____.
现有条件:
;
;
.请从这三个条件中任选一个补充在上面题干中,并解决下面问题.
(1)求数列
的通项公式;
(2)若
,求数列{bn}的前n项和
.
(注:如果选择多个条件分别解答,按第一个解答计分.)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
现有条件:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fbd39d2e3eeef71b04ec59f74b091e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf003ccc2fd8aa62b0d6a98d0666771a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a603fd1e721cae04e5c5c2014280edba.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/216876de04325fd250c38c485cbc34b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(注:如果选择多个条件分别解答,按第一个解答计分.)
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3 . 已知数列
满足
,且前12项和为134,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7999465d0e871febde66296a0cbf058c.png)
_____ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24892db4eaa5b54b3fc95dcba529d444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7999465d0e871febde66296a0cbf058c.png)
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名校
解题方法
4 . “不以规矩,不能成方圆”出自《孟子・离娄章句上》.“规”指圆规,“矩”指由相互垂直的长短两条直尺构成的方尺,是古人用来测量、画圆和方形图案的工具.敦煌壁画就有伏羲女娲手执规矩的记载(如图(1))今有一块圆形木板,以“矩”量之,如图(2).若将这块圆形木板截成一块四边形形状的木板,且这块四边形木板的一个内角
满足
,则这块四边形木板周长的最大值为______ (单位:厘米)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f8783429be686df75afcd56e847dfa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/7/7b52b3da-7f3b-4a55-8a4e-8b9121cb4e82.jpg?resizew=283)
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5 . 如图,已知两座山的海拔高度
米,
米,在BC同一水平面上选一点
,测得
点的仰角为
点的仰角为
,以及
,则M,N间的距离为____________ 米.(结果保留整数,参考数据
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd9cbea10075834324a661a4514c4e02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/664ef8298f9c6eef667861e1da9bd8a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96826763a0ea52872b73c25460e2d973.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c030b25575d683af91c06e6a3e4f463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08fddda4936a9be50e32b18b4c79e8b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e37ef1a48dbbf1c399ece970d3a92c.png)
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6 . “中国剩余定理”又称“孙子定理”,原文如下:今有物不知其数,三三数之剩二(除以3余2),五五数之剩三(除以5余3),七七数之剩二(除以7余2),问物几何?现有这样一个相关的问题:已知正整数p(p>1)满足二二数之剩一,三三数之剩一,将符合条件的所有正整数p按照从小到大的顺序排成一列,构成数列
,记数列
的前n项和为
,则
的最小值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87bbdd99442cbbc3b8610793c384af1a.png)
A.16 | B.22 | C.23 | D.25 |
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7 . 已知数列{an}的前5项依次为
,则
的一个通项公式为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
____________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a5dd3afeace11dffe48c4ecde8436f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
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8 . 若数列
是等比数列,且
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e81c85c03636630979bd90a4f6627e5.png)
A.数列![]() |
B.数列![]() |
C.数列![]() |
D.数列![]() |
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9 . 设数列
为正项等比数列,
为公比,
为前
项的积,且
,
,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/115da54f93de5e89d1e7f443fccb61f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/183717ba05a0a954db7233f20c04262b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/928cca3d16082f989ed38ba12b6f562f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dba40b59fa9e90c0ec1034730b2d596.png)
A.![]() |
B.![]() |
C.![]() |
D.![]() ![]() ![]() |
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10 . 刚考入大学的小明准备向银行贷款a元购买一台笔记本电脑,然后上学的时候通过勤工俭学来分期还款.小明与银行约定:每个月月末还一次款,分12次还清所有的欠款,且每个月还款的钱数都相等,贷款的月利率为t.则小明每个月所要还款的钱数为( )元.
A.![]() |
B.![]() |
C.![]() |
D.![]() |
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