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如图,OA⊥OB,等腰直角三角形CDE的腰CD在OB上,∠ECD=45°,将三角...
如图,OA⊥OB,等腰直角三角形CDE的腰CD在OB上,∠ECD=45°,将三角形CDE绕点C逆时针旋转75°,点E的对应点N恰好落在OA上,则
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的值为( )
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A.
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B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193857253480427/SYS201311011938572534804001_ST/2.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193857253480427/SYS201311011938572534804001_ST/3.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193857253480427/SYS201311011938572534804001_ST/4.png)
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