如图1,△ABD和△AEC均为等边三角形,连接BE、CD.
(1)请判断:线段BE与CD的大小关系是______;
(2)观察图2,当△ABD和△AEC分别绕点A旋转时,BE、CD之间的大小关系是否会改变?
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000342952766278/SYS201311030003429527662020_ST/images0.png)
(3)观察图3和4,若四边形ABCD、DEFG都是正方形,猜想类似的结论是______,在图4中证明你的猜想;
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000342952766278/SYS201311030003429527662020_ST/images1.png)
(4)这些结论可否推广到任意正多边形(不必证明),如图5,BB
1与EE
1的关系是______;它们分别在哪两个全等三角形中______;请在图6中标出较小的正六边形AB
1C
1D
1E
1F
1的另五个顶点,连接图中哪两个顶点,能构造出两个全等三角形?
考点分析:
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