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(2006•襄阳)在Rt△ABC中,∠C=90°,若AB=2AC,则cosA的值...
(2006•襄阳)在Rt△ABC中,∠C=90°,若AB=2AC,则cosA的值等于( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349019_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349019_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349019_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349019_ST/3.png)
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