1 . 某制冷设备厂设计生产一种长方形薄板,如图所示,长方形
的周长为4米,沿
折叠使
到
位置,
交
于
,研究发现,当
的面积最大时最节能,则最节能时
的面积为
![](https://img.xkw.com/dksih/QBM/2018/11/8/2071040489955328/2071204799152128/STEM/6f161fc55aa1471fb0c931fcb879f984.png?resizew=167)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c5d54dfb9237412a7c1c00658830de6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59ac8c5700ce2de9a140c4adea742168.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cd51caff8d6cd6d3478fb4659789d8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/2018/11/8/2071040489955328/2071204799152128/STEM/6f161fc55aa1471fb0c931fcb879f984.png?resizew=167)
A.![]() | B.![]() | C.![]() | D.2 |
您最近一年使用:0次
名校
解题方法
2 . 如图所示,平面四边形
的对角线交点位于四边形的内部,
,
,
,
,当
变化时,对角线
的最大值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f144992e1cbee34868abce1e5ad38c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/212bfbd5575772ca36d6fc3e7b246e49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf10d92f20501e19d25f6f4159aab89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/12/eefc0643-5c92-4638-9b11-091c8ba433fa.png?resizew=129)
您最近一年使用:0次
2018-02-09更新
|
1694次组卷
|
5卷引用:河北省定州中学2018届高三毕业班下学期开学考试数学试题
名校
解题方法
3 . 如图,在
中,
,
,等边
三个顶点分别在
的三边上运动,则
面积的最小值为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/16/e49f4ab6-6758-46e5-b1dc-9e7cd50b1b62.png?resizew=166)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ccc37b189fa2cbc269ca0b233dac37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa40241bbc16349eb7b611dedd09afbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5e61804ce550636a0354e0a78a22d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/16/e49f4ab6-6758-46e5-b1dc-9e7cd50b1b62.png?resizew=166)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2017-09-06更新
|
2309次组卷
|
3卷引用:河北省定州市定州中学2018届高三上学期第二次月考数学试题