1 . 在等差数列
中,
,
.
(1)求
的通项公式;
(2)求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/888cc0e4792d7fdbd704837a26fd0b7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/feff63be81acfd0efa846fe6098118e2.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b91adba8efbf964e9e35547b0fd0ea36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
2021-12-27更新
|
797次组卷
|
2卷引用:吉林省白山市2021-2022学年高二上学期期末数学试题
名校
解题方法
2 . 在等差数列
中,
,
,其前n项和为
.
(1)求
的最小值及此时
的值;
(2)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd0ad2b7696e9e8097a80cb1d617206.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09234d7ed84cf5d7b43da57dd335ce78.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d79e561b942febb191e8abeb9d222dbe.png)
您最近一年使用:0次
2020-10-07更新
|
579次组卷
|
6卷引用:吉林省白山市抚松县第一中学2021-2022学年高二上学期第三次月考数学试题