如图,在四棱锥
中,四边形
是边长为2的菱形,
,
平面
,
是
的中点,
是
的中点,
.
![](https://img.xkw.com/dksih/QBM/2021/4/28/2709572373741568/2735547786174464/STEM/80799278-1b81-4b0e-bbdb-fa958c7959ad.png?resizew=228)
(1)求证:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee296a7d9fba487f1485c61580196f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829f9180ddd9aa1a0ee0dc520f4e0b5f.png)
![](https://img.xkw.com/dksih/QBM/2021/4/28/2709572373741568/2735547786174464/STEM/80799278-1b81-4b0e-bbdb-fa958c7959ad.png?resizew=228)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05d2c1b3fd7524383736c72f4c0f1f27.png)
更新时间:2021-06-04 07:49:07
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,底面
是矩形,
,
,
,点M,N分别是棱
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/14a9794d-fe9e-42c8-9789-0997087626a5.png?resizew=199)
(1)求证:
平面
;
(2)若平面
平面
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3912bd0b4aad85d86a46fb846cc04596.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f36bd3b2701a86536663fbe6b65a7c61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb37aafadd6fcfac81dba37b6f45fabb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/14a9794d-fe9e-42c8-9789-0997087626a5.png?resizew=199)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,在多面体ABCDEF中,四边形ABCD是正方形,
,
是
的中点.
平面BDM;
(2)若
平面
,点
为线段CE上一点,且
,求直线PM与平面AEF所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8672344d01fe561aefebceea7af3aa5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9f79d7939c88e9702962e5917cad290.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a7e36a62ef674140e31c1ba4f1fe2ce.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1100a56e918f75ed6d955a802050f9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5019344a09a1a584b1be03c29223a29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce797f8d00de0d98b20605ca219df205.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,四棱柱
的底面
为矩形,
为
中点,平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/27/d7c36398-c2fd-47ec-88ab-5e6ce625c309.png?resizew=177)
(1)证明:
平面
;
(2)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5e29ca242ec45e8932247be58c633a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a45953045e613b97eeee15ac188ae2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb119c89f01ba89c7f1684f75957736b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/27/d7c36398-c2fd-47ec-88ab-5e6ce625c309.png?resizew=177)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4890e58791814622b87c4d60ea971f54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/530bca33e52e5d0108885ff4e6978863.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,在四棱锥
中,
底面
,
.点A在平面
内的投影恰好为
的重心E,连接
并延长交
于F.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/18/5e634c1e-b566-4002-9928-8e0de73d0b14.png?resizew=155)
(1)求证:
;
(2)求平面
与平面
所成夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/369edd6b016e161f30a2100f80e33d39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c71b0435044e0958d82e10cf0b81cb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05e78042a384255038de485fd7bc0839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5adb5eb60ae4435a12d93854066298.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/18/5e634c1e-b566-4002-9928-8e0de73d0b14.png?resizew=155)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdf23e73ae2a15c04bbed3981cb8e511.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
您最近一年使用:0次