计算![](https://staticzujuan.xkw.com/quesimg/Upload/formula/973fd8ae96e73fd27935c190a243358a.png)
________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/973fd8ae96e73fd27935c190a243358a.png)
更新时间:2017-10-14 21:49:05
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【知识点】 求等差数列前n项和
相似题推荐
填空题-单空题
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适中
(0.65)
真题
【推荐1】设等差数列
的前
项和为
.若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/243ea86129794af607ad88f444ac8e89.png)
___________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/853446ad8baabe4eac25b7875747603f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/698f35aef8c7e2aadaa18cda0fc2f24c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/243ea86129794af607ad88f444ac8e89.png)
您最近一年使用:0次
【推荐2】已知数列
的首项为4,且满足
,则下列结论中正确的是______ .(填序号)
①
为等差数列;②
为严格增数列;③
的前n项和
;④
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a89ba78941008c9504c98ee6daf331e.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bf3da897eb73b729f66bb0d700775c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d97d0115675a7a748069f3041417eb68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2c51408902bbd3540fafc89f6c9adff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bd55bf49836da72171eed2c2d244812.png)
您最近一年使用:0次