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如图,⊙O的直径AB与弦AC的夹角为30°,切线CD与AB的延长线交于点D,若⊙...
如图,⊙O的直径AB与弦AC的夹角为30°,切线CD与AB的延长线交于点D,若⊙O的半径为2,则CD的长为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430783921/SYS201311031008504307839006_ST/images0.png)
A.2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430783921/SYS201311031008504307839006_ST/0.png)
B.4
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430783921/SYS201311031008504307839006_ST/1.png)
C.2
D.4
考点分析:
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