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如图,AB是⊙O的直径,AC是⊙O的切线,A为切点,连接BC交圆O于点D,连接A...
如图,AB是⊙O的直径,AC是⊙O的切线,A为切点,连接BC交圆O于点D,连接AD,若∠ABC=45°,则下列结论正确的是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430596311/SYS201311031008504305963019_ST/images0.png)
A.AD=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430596311/SYS201311031008504305963019_ST/0.png)
BC
B.AD=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103100850430596311/SYS201311031008504305963019_ST/1.png)
AC
C.AC>AB
D.AD>DC
考点分析:
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