挑战习题
1/5单选题
难度:

1.

已知,如图边长为3的正方形ABCD绕点C按顺时针方向旋转30°后得到正方形EFCG,EF交AD于点H,

那么DH的长为(     )

青果学院


A

B

C

D

提示1:
PHA+5qC55o2u5peL6L2s55qE5oCn6LSo5b6X4oigQkNGPTMwwrDvvIxDQj1DRj0z77yM4oigRj3iiKBCPTkwwrDvvIzliJnlj6/moLnmja7igJxITOKAneWIpOaWrVJ04pazQ0hG4omMUnTilrNDSETvvIzmiYDku6XiiKBGQ0g94oigRENIPTMwwrDvvIznhLblkI7moLnmja7lkKszMOW6pueahOebtOinkuS4ieinkuW9ouS4iei+ueeahOWFs+ezu+axguinozwvcD4=
正确答案:QQ==
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