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(2002•四川)如图,在Rt△ABC中,∠ACB=90°,CD⊥AB于D,AC...
(2002•四川)如图,在Rt△ABC中,∠ACB=90°,CD⊥AB于D,AC=2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463421933/SYS201310212326024634219006_ST/0.png)
,AB=2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463421933/SYS201310212326024634219006_ST/1.png)
,设∠BCD=α,那么cosα的值是( )
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A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463421933/SYS201310212326024634219006_ST/2.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463421933/SYS201310212326024634219006_ST/3.png)
C.
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D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463421933/SYS201310212326024634219006_ST/5.png)
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