在正三棱柱
中,
,
,
分别为
,
的中点,则异面直线
与
所成角的余弦值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92105835f8075cb75dff244e908370b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee16c91119c5601a7c93a6642c95e7f8.png)
更新时间:2019-04-23 19:56:52
|
【知识点】 求异面直线所成的角
相似题推荐
填空题-单空题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在棱长为2的正方体
中,
,
分别为棱
,
的中点,给出下列五个命题:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/0370afaa-7aec-4ca8-89df-92e587e4d907.png?resizew=208)
①
,
所成的角为
;
②
;
③三棱锥
的外接球的表面积为
;
④平面
截正方体所得的截面是等腰梯形;
⑤以点
为球心,
为半径作球面,则该正方体表面被球面所截得的所有弧长的和为
;
其中真命题是___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/0370afaa-7aec-4ca8-89df-92e587e4d907.png?resizew=208)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9955b5aebb73cd84447e8541f901ac.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d456847f7a9db41ffb1486e2cfe580d7.png)
③三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5315b0db36b8716f3de7336120384fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4986217611fc5eefe70fd217a9d5726a.png)
④平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/212a67f115d1cbe69f100b489babe5f8.png)
⑤以点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14c055a02fba0827ffcaa92f73ce7720.png)
其中真命题是
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
解题方法
【推荐2】在正四面体中,
分别为棱
,
的中点,过
和侧面
内的一点
的平面分别与
,
交于
点,则直线
与
所成角的大小为
您最近一年使用:0次