1 . 在正项无穷数列
中,若对任意的
,都存在
,使得
,则称
为
阶等比数列.若
为1阶等比数列,且
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
_________ ;若数列
是2阶等比数列,且
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6016be828be0c8e87f425f3b9437ba1.png)
_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209559aca6bf32705588b6a40e0b7320.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49f62d620374c35e1d8d90b6f8b6e801.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a327da06d8bf19a6f0ce10089cf303d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a9e8b2a0eed594720eb8a65fefd714a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0223546f654f83bb6ebf4bb52e86157.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3f7fda69e2b32b9ced2239f915fa59b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd6c97d2ee3e74ba5730f1cbcc1d43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1bfdf0c734162745dcebe626bc59cc0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd4cf909f2febeea7d169459d0cf0bcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6016be828be0c8e87f425f3b9437ba1.png)
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2 . 已知向量在向量
上的投影向量的模为
,则
为整数的n的值按照从小到大的顺序排列,得到的新数列的前n项和
您最近一年使用:0次
2024-03-21更新
|
229次组卷
|
2卷引用:广西百所名校2023-2024学年高二下学期入学联合检测数学试题
解题方法
3 . 设等比数列
的公比为
,其前
和为
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
__________ ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614306cc3f34bdee4d5d885b79667645.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c22c96b4d06bc3172cbeb08f4e8c4d2.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/88b87180760dacba44b0441f22686993.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614306cc3f34bdee4d5d885b79667645.png)
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4 . 设等差数列
的前n项和为
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c2864e2ec3416cc4c081ac1f71a0af.png)
______ ,使
为整数的正整数n的值的个数为______ .
![](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/3d5efd820db11512606d98aaa9b1b424.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f6fef5b0cd6f3ad1a92b1a767452bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c2864e2ec3416cc4c081ac1f71a0af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5cc400b008302822d916e0a68311ae7.png)
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名校
解题方法
5 . 已知递增等差数列{an},其前n项和为Sn,
,则当公差d的值为__________ 时,S13的最小值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71cd840e920721863a3bdfb454c8eacb.png)
您最近一年使用:0次
2020-11-05更新
|
203次组卷
|
5卷引用:广西桂林市广西师范大学附属2021届高三年级上学期数学第三次月考试题
广西桂林市广西师范大学附属2021届高三年级上学期数学第三次月考试题(已下线)专题08 基本不等式(客观题)-2021年高考数学(理)二轮复习热点题型精选精练(已下线)专题08 基本不等式(客观题)-2021年高考数学二轮复习热点题型精选精练(新高考地区专用)(已下线)专题08 基本不等式(客观题)-2021年高考数学(文)二轮复习热点题型精选精练苏教版(2019) 选修第一册 选填专练 第4章 微专题八 等差数列的性质及其应用
名校
6 . 下表数阵的特点是每行每列都成等差数列,记第i行第j列的数为
则(1)![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64b0edc3daafba0a8fb5843d0a1f9ab3.png)
_____ (
);(2)表中的数52共出现________ 次.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0f241c63967d02257754086704a5bf5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64b0edc3daafba0a8fb5843d0a1f9ab3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
2 | 3 | 4 | 5 | 6 | 7 | … |
3 | 5 | 7 | 9 | 11 | 13 | … |
4 | 7 | 10 | 13 | 16 | 19 | … |
5 | 9 | 13 | 17 | 21 | 25 | … |
6 | 11 | 16 | 21 | 26 | 31 | … |
7 | 13 | 19 | 25 | 31 | 37 | … |
… | … | … | … | … | … | … |
您最近一年使用:0次
2020-09-22更新
|
144次组卷
|
2卷引用:广西桂林市第十八中学2020-2021学年高二上学期开学考试数学试题