如图,在四棱锥
中,底面
为直角梯形,
,
,
,平面
平面
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/fa2659cf-c5f3-4a72-8650-434be07285c0.png?resizew=243)
(1)证明:
平面
;
(2)求平面
与平面
所成锐二面角的余弦值.
![](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/4db335d71f1cd3514a99faa896dfded6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa7aeb2a8d1437eeb4482c3b6ad9f315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/533865d9ae72af3a022cce4dfa3f907b.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/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/fa2659cf-c5f3-4a72-8650-434be07285c0.png?resizew=243)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/982d01f052709b72afeaf1015fc7acc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
更新时间:2022-05-11 17:09:00
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,在几何体
中,四边形
是边长为2的正方形,
,
,点
在线段
上,且
.
平面
;
(2)若
平面
,且
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/139605ce39f25ecd96cdcdad7364adb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d927585a17c2e98ef7d5a9589a26ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57233d035f8df0be96001431bf009a87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77e64cd7d049fd830287a6fb6b3a5870.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea848cd2aa3a464618020475097949fc.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69bcb3226e013650b7d8827c31dd41d0.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐2】正三棱柱
中,
是棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/264ab817-bc7f-4ce8-b36d-769e2a70f350.png?resizew=146)
(Ⅰ)求证:
平面
;
(Ⅱ)设
,
,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/264ab817-bc7f-4ce8-b36d-769e2a70f350.png?resizew=146)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1496afecd92a619fbe5e9b736f06f4e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2a0a3bb566b5d2404e4bb823abddfa9.png)
(Ⅱ)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6db57eca2a7cbd91bc57372592580a76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2a0a3bb566b5d2404e4bb823abddfa9.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐3】如图,已知三棱柱
中,侧棱与底面垂直,且
,
分别是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/13/044137f3-67f1-4350-928d-693b862a75f5.png?resizew=159)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
平面
;
(2)求平面
与平面
夹角的余弦值;
(3)点
在线段
上,若直线
与平面
所成角的余弦值为
时,求线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3275dc6ee54ee3f1606e7b491a6a27ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9d6e5b1970f8c445be8925e10105ebd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88a2eab2323b9e1a46d0f1c834eb7b97.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/13/044137f3-67f1-4350-928d-693b862a75f5.png?resizew=159)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a9bfa68259d7a331be323b2038d628a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f2af0a097c6c0870b0db6a9bec14e4f.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22ce50ba5e349425274f05d46d120a74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(3)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22064b7c5fdc0cd58905f49cc480b4e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40aa9bd446815b9b94a3b4623ba576b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e935bb9d7b7115429edbd1e7469af65.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,在四棱锥P-ABCD中,PA⊥平面ABCD,在四边形ABCD中,∠ABC=
,AB=4,BC=3,CD=
,AD=2
,PA=4.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/d8f58f59-2453-4fa9-93c9-ab0402323dea.png?resizew=148)
(1)证明:CD⊥平面PAD;
(2)求二面角B-PC-D的余弦值..
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1ad72d7565699d1ebb741eb0ce12bac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/5/d8f58f59-2453-4fa9-93c9-ab0402323dea.png?resizew=148)
(1)证明:CD⊥平面PAD;
(2)求二面角B-PC-D的余弦值..
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】如图,在底面为正方形的四棱锥
中,
平面
,点
,
分别在棱
,
上,且满足
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/98976519-c653-40b0-ad8b-aa0bad9dff9e.png?resizew=141)
(1)证明:
平面
;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662698361c6b3ddaf0c28a3c87be53e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84f31a3724c639f88486f8356ca65397.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ae1f526d7db5cf15d808c8ca6078659.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/6/98976519-c653-40b0-ad8b-aa0bad9dff9e.png?resizew=141)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a779876cdfb2c489ad0eaed0f73e6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e92f48e9bfe12d145f7d2a2f0360d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52cc255734ed3b4563750e15dcdb0869.png)
您最近一年使用:0次