阅读与理解:
图①是边长分别为
和
(
)的两个等边三角形纸片
和
叠放在一起(点
与点
重合)的图形.
操作与证明:
(1)操作:固定
,将
绕点
按顺时针方向旋转
,连接
、
,如图②,在图②中,线段
与
之间具有怎样的大小关系?证明你的结论;
(2)操作:若将图①中的
绕点
按顺时针方向任意旋转一个角度
,连接
、
,如图③,在图③中,线段
与
之间具有怎样的大小关系?证明你的结论;
猜想与发现:
根据上面的操作过程,请你直接写出当
为多少度时,线段
的长度最大,最大是多少?
图①是边长分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/787ac5e13622afab5e9f8603afe42356.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d61b279d8e19b6f74a79d249d66fe4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4c8a9c4957431681ddfc77895a88508.png)
操作与证明:
(1)操作:固定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/549e807ed5636b783c51603d38337313.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c030b25575d683af91c06e6a3e4f463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0213c5787a5a6b38d11bceca5567f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0213c5787a5a6b38d11bceca5567f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
(2)操作:若将图①中的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/549e807ed5636b783c51603d38337313.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0213c5787a5a6b38d11bceca5567f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0213c5787a5a6b38d11bceca5567f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
猜想与发现:
根据上面的操作过程,请你直接写出当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88929f4ba0851730d5f941d426b87548.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/16/dc4ead81-51eb-46f0-9c3f-cf4678e163a9.png?resizew=435)
更新时间:2024-01-16 18:44:05
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![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/10/1505eac4-ff01-4bb5-899c-72edbba50d19.png?resizew=313)
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