首页 / 已知正三角形的边长为12，则这个正三角形外接圆的半径是A．    

已知正三角形的边长为12，则这个正三角形外接圆的半径是A．    

已知正三角形的边长为12，则这个正三角形外接圆的半径是

A．          B．           C．         D．

 

答案

C

解析:略

 

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