解题方法
1 . 已知
=1,
=2,且
与
的夹角为
,则
= ( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94d723baf90e91b4691a2dcdd8f2a53e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc7d8b42c85013ba07ba18e5e46d8716.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb74499b8965b3f6c9acfbbb168df438.png)
A.13 | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
解题方法
2 . 若向量
,
是单位向量,且
,则向量
与
的夹角为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b28baf17059c56ee9ad1ae4814acd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b04618e5b2db68f2de6ba68972c505c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f86f1d3dd83afdae048166c0c2effd9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b28baf17059c56ee9ad1ae4814acd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b04618e5b2db68f2de6ba68972c505c.png)
A.150° | B.120° | C.60° | D.30° |
您最近一年使用:0次