如图,在三棱锥
中,
底面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/29/6c27cf44-4bf4-4a15-acea-dfe23eedfdf1.png?resizew=161)
(1)证明:平面
平面
;
(2)若
,直线
与平面
所成角的大小为
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41e5db1d2fd912f77923e4c120a7dc19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10c83f8945042b9c8fb2fbdac9308d62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42deb6707a04e7810c10a8370f2422d2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/29/6c27cf44-4bf4-4a15-acea-dfe23eedfdf1.png?resizew=161)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b6e6192cf24ada791c26c2d6d434069.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc9c9cfa597b444b5c9dbae7a825a695.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21665d21bbfb04410c78345de1fd15ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a6e2867f32d3f1c3cd36cd3a11a8580.png)
更新时间:2022-06-23 12:24:40
|
相似题推荐
解答题-证明题
|
较易
(0.85)
名校
解题方法
【推荐1】如图,在三棱柱
中,四边形
为矩形,
,
,点E为棱
的中点,
.
![](https://img.xkw.com/dksih/QBM/2021/11/25/2858973959184384/2859636686659584/STEM/f8f10794056c49599443e11a9701ec1d.png?resizew=187)
(1)求证:平面
平面
;
(2)求平面AEB与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9bfdc3ed1111f2603f33f58a161d758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72c5b2dcbc4826df1c1857f50b85767f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b0393ce62b24aa5f9b740d4cc6743b.png)
![](https://img.xkw.com/dksih/QBM/2021/11/25/2858973959184384/2859636686659584/STEM/f8f10794056c49599443e11a9701ec1d.png?resizew=187)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d7090639341730951c1bc3c9b6164e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(2)求平面AEB与平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea86090c412d8ab5f1e5f974329319ce.png)
您最近一年使用:0次
【推荐2】如图,底面是平行四边形的四棱锥
中,点
是线段
上的点,
平面
,
平面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2020/2/18/2401669072846848/2401920139059200/STEM/79eaa02bc53c4767a863595352b9d84c.png?resizew=264)
(1)求证:点
是
中点;
(2)求证:平面
平面
;
(3)求三棱锥
底面
上的高.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffc3380658a60e5c139bc30572e0e98c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.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/6bbd7c2767c106faf27d6a97ebc8e739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a9b8e7befcb7881c294070175b1a554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d4746df85049d1651d3f6c30212a7a9.png)
![](https://img.xkw.com/dksih/QBM/2020/2/18/2401669072846848/2401920139059200/STEM/79eaa02bc53c4767a863595352b9d84c.png?resizew=264)
(1)求证:点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45d492a2248463e0c0199a25d0f76d23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.png)
您最近一年使用:0次
【推荐1】如图,长方体
中,
,
与底面
所成的角为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a97bb4dcfab4ec7539bc783d563c49.png)
(1)求四棱锥
的体积;
(2)求异面直线
与
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb4957406b21df59fdf7fa184752287b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a97bb4dcfab4ec7539bc783d563c49.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/24/4652ab89-e079-485e-8dc9-73e01cfbc261.png?resizew=148)
(1)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e2e341788ce1be913bc47b3831c6baa.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cfbc0b5a8fbde804bd8425a4b76d207.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
名校
解题方法
【推荐2】如图,四棱锥
的底面
是边长为2的正方形,平面
平面
,
是斜边
的长为
的等腰直角三角形,
,
分别是棱
,
的中点,
是棱
上一点.
![](https://img.xkw.com/dksih/QBM/2021/8/28/2796113323352064/2798969608798208/STEM/22b396ae-e112-4764-8166-f0d18e1a2934.png?resizew=227)
(1)求证:平面
平面
;
(2)若直线
与平面
所成角的正切值为
,求锐二面角
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/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2021/8/28/2796113323352064/2798969608798208/STEM/22b396ae-e112-4764-8166-f0d18e1a2934.png?resizew=227)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62cce4195e4e9045821a4a9e79a151cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/907d5147cea4c9ce855074864fe54506.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edbb52befa94a9f54e6f3e3125918016.png)
您最近一年使用:0次