1 . 在等差数列
中,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5170584604571b5e1afd5ece941e2e73.png)
(1)求
的通项公式
;
(2)求
的前n项和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5170584604571b5e1afd5ece941e2e73.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb007620a97b6b556e9b1f50abb9eb72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
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2016-12-04更新
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2卷引用:2015-2016学年四川广安邻水等区县高一下期末联考数学(理)试卷
2 . 等差数列
中,若
则公差
=
![](https://img.xkw.com/dksih/QBM/2015/8/13/1572212755914752/1572212761108480/STEM/5d1a3099771743d8a85b601365f8253d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1e9f9872e36a8a92093555f606078fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
A.3 | B.6 | C.7 | D.10 |
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2016-12-03更新
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1207次组卷
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8卷引用:2014-2015学年四川省宜宾市高一下学期期末测试数学试卷
3 . 如果数列
满足
=1,当
为奇数时,
;为偶数时,
,则下列结论成立的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02ce9d5623b21817dd182b9058dc271a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffb3518bca5f88605691f7c909183450.png)
A.该数列的奇数项成等比数列,偶数项成等差数列 |
B.该数列的奇数项成等差数列,偶数项成等比数列 |
C.该数列的奇数项各项分别加![]() |
D.该数列的偶数项各项分别加![]() |
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2016-12-03更新
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5卷引用:四川省自贡市2021-2022学年高一下学期期末考试数学(文)试题
四川省自贡市2021-2022学年高一下学期期末考试数学(文)试题2014-2015学年重庆市万州二中高一4月月考文科数学试卷上海市行知中学2015-2016学年高一下学期6月月考数学试题(已下线)知识点 等比数列通项公式 易错点 忽视奇数项符号相同、偶数项符号相同(已下线)专题5-2数列递推及通项应用-3