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如图,正棱柱ABCD-A1B1C1D1中,AA1=2AB,则异面直线A1B与AD...
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如图,正棱柱ABCD-A
1B
1C
1D
1中,AA
1=2AB,则异面直线A
1B与AD
1所成角的余弦值为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065555259/SYS201311012311270655552004_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065555259/SYS201311012311270655552004_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065555259/SYS201311012311270655552004_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065555259/SYS201311012311270655552004_ST/3.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065422560/SYS201311012311270654225020_ST/0.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231127065422560/SYS201311012311270654225020_ST/4.png)
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