在等差数列
中,
,其前n项和为
,则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6227da2c8ba612ccab7c993c2674fe01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3cf6f2bbe20a404fea41a4d2b1c4c7.png)
A.10 | B.55 | C.100 | D.110 |
更新时间:2021-12-30 13:31:02
|
相似题推荐
单选题
|
较易
(0.85)
解题方法
【推荐1】设
为等差数列
的前n项和,若
,且
.则使
的n的最小值为( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3ccd6ddbc590241bc301b87ffc03335.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/937228faf3b035ce9fb607ec96f707f0.png)
A.30 | B.31 | C.32 | D.33 |
您最近一年使用:0次
单选题
|
较易
(0.85)
解题方法
【推荐2】已知等差数列
的前
项和为
,若
,则使
成立的
的最大值为( )
![](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/3573233ae980c360fee275e6f4e173c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49763402b2f2023f0ba64c37924267d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
A.3 | B.4 | C.5 | D.6 |
您最近一年使用:0次
单选题
|
较易
(0.85)
解题方法
【推荐1】已知数列
的前
项和为
,
,
,且对于任意
,
,满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1741e9b4bf47139c7363dff730d1c08.png)
,则
的值为( )
![](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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c9b6e51986fe5d7a7265e0e93adcb4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67b0d8ecf4955dfcb76ca3e896568b7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1741e9b4bf47139c7363dff730d1c08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e0f6a0f7f5a1e1236040bd732b8d04e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3cf6f2bbe20a404fea41a4d2b1c4c7.png)
A.90 | B.91 | C.100 | D.101 |
您最近一年使用:0次
单选题
|
较易
(0.85)
名校
解题方法
【推荐2】设等差数列
的前n项和为
,且
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
![](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/a4be9a388b7f772af8dc8407c7951536.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfd9924ca4f098fa6987dfa6682c39ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc4e70b360f988fdbd92300ab22c4613.png)
A.9 | B.12 | C.![]() | D.![]() |
您最近一年使用:0次