1 . 已知等差数列
,
,则
的值为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8c9eb4582f92423a560f86e5211434a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d77e09e726455ad7ad223c34f0fe6373.png)
您最近一年使用:0次
2022-12-03更新
|
1596次组卷
|
3卷引用:海南省儋州市川绵中学2022-2023学年高二下学期期中检测数学试题
名校
2 . 已知等差数列
的前
项和为
,若
,则
( )
![](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/73a2b7d4d967ffe1d0affe538f286890.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bca8f26c7e2cf5c7c4eaf39b089ae52.png)
A.80 | B.90 | C.100 | D.110 |
您最近一年使用:0次