1 . 已知等差数列
的首项
为首项2的等比数列,且公比大于0.
.
(1)分别求
的通项公式;
(2)求数列
的前
项和
;
(3)令
,判断
有无最大项,若有指出第几项最大,求最大项的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d835aa342d7edf121fc1ed4f37fe14a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1332967e6c6b353f3418663fddedf26f.png)
(1)分别求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62e567d7e9761951a266953c8d5042ac.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5344eadd4711db34e3f935aedd5fb270.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
(3)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1a3778befd5dfec1f5206a679286dd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c59e7c7a84a4bdb959e95536d0404ceb.png)
您最近一年使用:0次
名校
解题方法
2 . 已知数列
的前
项和为
.
(1)求数列
的通项公式
;
(2)若
,
,求
;
(3)记
,若数列
中去掉数列
中的项后余下的项按原来的顺序组成数列
,求
的值.
![](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/5eb7cc43cfb7b80699bca2f523434d85.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9d803ea42100a942e02f29145ce98b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b519f2287a07079f6ca20588d06171f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4537fdbb4055cb3d0129526cc93cecd.png)
(3)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f62394979f2e6c479e60d7b350b2328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b783cf91e34e692ce8e171f0965cb53f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb4dff95b024b3161a52dfc594afe461.png)
您最近一年使用:0次
2022-12-12更新
|
426次组卷
|
2卷引用:上海市第三女子中学2021-2022学年高一下学情期末数学试题
3 . 下列命题中,真命题的个数是( )
(1)若数列
是等比数列,则数列
也是等比数列.
(2)若
,则
或
.
(3)
.
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa0dc13236eaa2bd0cdc0f24beea11fe.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5addd0c822fa3c5ac9c7db649f6682cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/364928ad04a33d667c8e9c62bf2d69ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c3c69c9d77fde225ce13154cb95c826.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70a1c5a68277243b33c8dc8e1fa03a85.png)
A.0 | B.1 | C.2 | D.3 |
您最近一年使用:0次
名校
4 . 无穷等比数列
的首项为
,公比为
,前
项和为
,且
,则首项
的取值范围是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.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/63d1cc281522ae231d0414e4dc924df4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
5 . 已知等比数列
的的前
项和为
,且
,求
的值.
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3011d3fbe8ded2c7e075fd1eb30f27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05201ef79a5d5904f492845396fb5470.png)
您最近一年使用:0次
名校
解题方法
6 . 已知数列![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72939e47d07ca7973b538bf0cd3c4360.png)
(1)令
,求证:数列
是等比数列;
(2)若
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72939e47d07ca7973b538bf0cd3c4360.png)
(1)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5653b60d16ec4e653518f0562680250.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2812d9e1f00c614eddafb51d349ffd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38ef4c4439b36c2847b0056a116d56d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
2022-12-12更新
|
1177次组卷
|
5卷引用:上海市上海中学东校2021-2022学年高一下学期期末数学试题
上海市上海中学东校2021-2022学年高一下学期期末数学试题山东省菏泽第一中学2022-2023学年高二上学期12月月考数学试题(已下线)数列求和(已下线)江西省五市九校协作体2023届高三第一次联考文科数学试题变式题16-20第四章 数列章末重点题型归纳(4)
名校
解题方法
7 . 设数列
的前
项和为
,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb708a25d30954a0a50b01d59453bbe.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.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/7f3ce3863539a618a28853de3c5201d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb708a25d30954a0a50b01d59453bbe.png)
您最近一年使用:0次
名校
解题方法
8 . 设实数
,给出如下两个命题:
①存在
,使得
,
,
,
按某种顺序可组成等差数列;
②存在
,使得
,
,
,
按某种顺序可组成等比数列.
则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d1c7571006978c5115a9a6bd764698a.png)
①存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48345d239aaf8e9ca1ff2846c08a99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66db91bb3be9e2b6ad567774e3699758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99c5a05a11f731194a845e68a0479ce4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ada1a099b4cb4863ef1a94927c221ff8.png)
②存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48345d239aaf8e9ca1ff2846c08a99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66db91bb3be9e2b6ad567774e3699758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99c5a05a11f731194a845e68a0479ce4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ada1a099b4cb4863ef1a94927c221ff8.png)
则( )
A.①②均为真命题 | B.①为真命题,②为假命题 |
C.①为假命题,②为真命题 | D.①②均为假命题 |
您最近一年使用:0次
名校
9 . 在等比数列
中,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/deac43ca6faa7937931a3e0ad9cb1744.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0382b4a2ab0657d2d6830bb6be2b17b6.png)
A.![]() | B.2 | C.![]() | D.1 |
您最近一年使用:0次
名校
解题方法
10 . 已知复数
,
,其中
是实数.
(1)若在复平面内表示复数
的点位于第二象限,求
的取值范围;
(2)若
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0511fc1b903f8d95e7eea6e0c7ed0f04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ef85e50ad731ebb0837c8eabf32ce3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4887473a8091e1ef53a169cc9f211e3a.png)
(1)若在复平面内表示复数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af68f652b4c13657ffddf3c9e7eb262b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4887473a8091e1ef53a169cc9f211e3a.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e258ab9e600435b37465092243d99f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1c7d9c12ffc706115ae2d4364a2b64f.png)
您最近一年使用:0次