1 . 已知等差数列
满足
,
,则数列
的前6项的和
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dbd10104f790c96168b3c20f63254a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c32a54d94ca7db5bebdabfaa1a5f69b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d36243198e5e20c56399e4ad5ac3c519.png)
A.21 | B.25 | C.28 | D.32 |
您最近一年使用:0次
2021-01-03更新
|
342次组卷
|
3卷引用:广西南宁市2021届高三12月特训测试理科数学试题
名校
解题方法
2 . 记
为等差数列
的前
项和,若
,
,则
为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.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/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afbfd6b761451716ba3d7130c93497ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48e81b54f78b96294295542b010dfb.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2020-03-18更新
|
1002次组卷
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8卷引用:广西桂林市第十八中学2021届高三上学期第二次月考数学(文)试题