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已知∠BAC=45°,一动点O在射线AB上运动(点O与点A不重合),设OA=x,...
已知∠BAC=45°,一动点O在射线AB上运动(点O与点A不重合),设OA=x,如果半径为1的⊙O与射线AC有公共点,那么x的取值范围是( )
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A.0<x≤
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B.l<x≤
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C.1≤x<
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D.x>
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考点分析:
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