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如图,⊙O的弦AB=6,M是AB上任意一点,且OM最小值为4,则⊙O的半径为( ...
如图,⊙O的弦AB=6,M是AB上任意一点,且OM最小值为4,则⊙O的半径为( )
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A.5
B.4
C.3
D.2
考点分析:
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