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如图,⊙O的半径为1,点A是半圆上的一个三等分点,点B是弧的中点,P是直径MN上...
如图,⊙O的半径为1,点A是半圆上的一个三等分点,点B是弧
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164757970539178/SYS201310221647579705391004_ST/0.png)
的中点,P是直径MN上的一个动点,则PA+PB的最小值为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164757970539178/SYS201310221647579705391004_ST/images1.png)
A.1
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164757970539178/SYS201310221647579705391004_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164757970539178/SYS201310221647579705391004_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164757970539178/SYS201310221647579705391004_ST/3.png)
考点分析:
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