设等差数列
的前n项和为
,
,
;
(1)求数列
的通项公式;
(2)当
取最小值时,n的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a3f1f8813adcedd56b471961b2ad6a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c5b7ebdbceddc033fc579246b6c5bb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f4d9c96575985ca2ee98682064cb6a7.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a3f1f8813adcedd56b471961b2ad6a6.png)
更新时间:2023-02-25 13:28:46
|
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