1 . 设
是公比为
的无穷等比数列,
为其前
项和,
.则“
”是“
存在最小值”的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bbca32ee5e88a8e7163769c27836722.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f71acdb04454c77e1e25ad4f336cccfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
A.充分而不必要条件 | B.必要而不充分条件 |
C.充分必要条件 | D.既不充分也不必要条件 |
您最近一年使用:0次
2014·北京丰台·一模
名校
2 . 已知等比数列
中,
=1,
=2,则
等于.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d737c1047a14cee12a6671383e244fa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f9d2e152db0845ff23e4ea0cd00974d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4a13bd477c3e49fee39ee687d6323cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07cbd84c684b89714de542e4f19f9edc.png)
A.2 | B.2![]() | C.4 | D.4![]() |
您最近一年使用:0次
2016-12-02更新
|
1465次组卷
|
6卷引用:2014届北京市丰台区高三一模文科数学试卷