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如图,将含30°角的直角三角尺ABC绕点B顺时针旋转150°后得到△EBD,连接...
如图,将含30°角的直角三角尺ABC绕点B顺时针旋转150°后得到△EBD,连接CD.若AB=4cm.则△BCD的面积为
.
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