10-11高一·重庆江津·阶段练习
1 . 已知数列
是等比数列,且
则![](https://img.xkw.com/dksih/QBM/2011/12/29/1570668164268032/1570668169609216/STEM/7fa8c6a825ba4dc7a1b140cc69f01b19.png?resizew=47)
___
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/817d7150068932edf43958eea567809f.png)
![](https://img.xkw.com/dksih/QBM/2011/12/29/1570668164268032/1570668169609216/STEM/7fa8c6a825ba4dc7a1b140cc69f01b19.png?resizew=47)
您最近一年使用:0次
2011·重庆江津·三模
解题方法
2 . 已知向量
.
(1)若
三点共线,求实数
的值;
(2)若
为直角,求实数
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7605cae829e44f50c606b5a6da6ecc6a.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
您最近一年使用:0次
3 . 已知等差数列
满足
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb2ba519161267722f719f64994baf44.png)
_______________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/954bf29b19381de184bdd1a63b069dce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb2ba519161267722f719f64994baf44.png)
您最近一年使用:0次