名校
解题方法
1 . 如图,在棱长为4的正方体
中,E,F分别是
和
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/1b883abd-0146-4e83-9f78-a03bc185befd.png?resizew=160)
(1)求AC到平面BEF的距离;
(2)求平面
与平面BEF的夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/19/1b883abd-0146-4e83-9f78-a03bc185befd.png?resizew=160)
(1)求AC到平面BEF的距离;
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
您最近一年使用:0次