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已知向量,满足||=8,||=6,•=24,则与的夹角为( ) A.30° B....
已知向量
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/1.png)
满足|
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/2.png)
|=8,|
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/3.png)
|=6,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/4.png)
•
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/5.png)
=24,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/6.png)
与
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100906645361072/SYS201311031009066453610001_ST/7.png)
的夹角为( )
A.30°
B.60°
C.90°
D.120°
考点分析:
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