解题方法
1 . 若随机变量
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b260578876e57bd8298c45f77715566.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/221e8039aabd3cef924476edfe6c98ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e79f93023fa4c71ae88cceaefb2f0543.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b260578876e57bd8298c45f77715566.png)
您最近一年使用:0次
解题方法
2 . 四个面都为直角三角形的四面体称之为鳌臑.在鳌臑
中,
平面
,
,
,鳌臑
的四个顶点都在同一个球面上,则该球的表面积是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00bab2c27eac56fffa4cd7dbe1dcdf1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f121eabff3c62c1a196d9ca5f6f83f0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/8/22ea52e5-b353-4a6f-9cf6-dc130dff9c48.png?resizew=127)
您最近一年使用:0次