设
是
的二面角
内一点,
,
分别为垂足,
,则
的长为________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/754bbd99327195520a4ca3ce3b9a0577.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6eb1da12796ea10146af40f2e4bc603.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/221ac0460d842e2b7c1dd3aacd59a5e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
更新时间:2018-02-08 16:40:43
|
【知识点】 由二面角大小求线段长度或距离
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【推荐1】在二面角
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【推荐2】如图,位于山西省朔州市应县佛宫寺内的释迦塔,俗称应县木塔,是我国现存最高最古老的木结构塔式建筑,木塔顶部可以近似地看成一个正八棱锥,其侧面和底面的夹角大小为
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