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(2002•广西)在Rt△ABC中,∠ACB=90°,CD⊥AB垂足为D,且CD...
(2002•广西)在Rt△ABC中,∠ACB=90°,CD⊥AB垂足为D,且CD=3,AC=5,则cosB等于( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/3.png)
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