如图,
为圆
的直径,点
在圆
上,且
为等腰梯形,矩形
和圆
所在的平面互相垂直,已知
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/7/4f34f281-e539-40ec-87e0-bc0db3fc82da.png?resizew=153)
(1)求证:平面
平面
;
(2)当
的长为何值时,二面角
的大小为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dde327febef2331a4766a79b433cc02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29fb67185648985ee00f25b3332d7690.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/7/4f34f281-e539-40ec-87e0-bc0db3fc82da.png?resizew=153)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630675e0bd82419bc787b557181303d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/603c7e98deecdba0cf3773757a9b8304.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d733daf111889f16d5404b731d40fd12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/231b861d6d1f1d0b9f52b041cb40eb62.png)
更新时间:2023-02-04 23:23:15
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,
是圆
的直径,
是圆
上异于
,
的一点,
垂直于圆
所在的平面,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/20/97664393-4934-4ab6-8431-7f61b97a6d40.png?resizew=160)
(1)求证:平面
平面
;
(2)若
,求平面
与平面
所成的锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c64f3b6327eb3713198f8a32fd84bec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b092f74c792d4d50ddecf6be5b01333a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/20/97664393-4934-4ab6-8431-7f61b97a6d40.png?resizew=160)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e1e4ea140260a790885868bc7a94f2.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fb01d2b57580731c8b807ac8cffc8ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐2】如图,已知四边形ABCD是边长为2的菱形,∠ABC=60°,平面AEFC⊥平面ABCD,EF∥AC,AE=AB,AC=2EF.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/3/3b40f783-963a-4307-af29-69f0497db34a.png?resizew=157)
(1)求证:平面BED⊥平面AEFC;
(2)若四边形AEFC为直角梯形,且EA⊥AC,求二面角B-FC-D的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/3/3b40f783-963a-4307-af29-69f0497db34a.png?resizew=157)
(1)求证:平面BED⊥平面AEFC;
(2)若四边形AEFC为直角梯形,且EA⊥AC,求二面角B-FC-D的余弦值.
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解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,直三棱柱
中,
,
,
,点P在线段
上.
![](https://img.xkw.com/dksih/QBM/2022/1/19/2897962610122752/2899874628042752/STEM/f8dbc5c9-451a-424f-9c8b-39c371da3a2b.png?resizew=146)
(1)若P为
的中点.证明:
平面
;
(2)是否存在点P,使得平面
与平面ABC所成的二面角为
?若存在,试确定点P的位置;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a355958abf7dc0f2eb949584cb87907b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1602c3d3e9628cd503a443024410e87a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92105835f8075cb75dff244e908370b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/2022/1/19/2897962610122752/2899874628042752/STEM/f8dbc5c9-451a-424f-9c8b-39c371da3a2b.png?resizew=146)
(1)若P为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4560fa4ad459b58b723c74bd24e51ebf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f320511883ba5de9b71fd4f2c6edafab.png)
(2)是否存在点P,使得平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f320511883ba5de9b71fd4f2c6edafab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
名校
解题方法
【推荐2】如图甲,在等腰梯形
中,
,
,
是
的中点.将
沿
折起,使二面角
为
,连接
,
得到四棱锥
(如图乙),
为
的中点,
是棱
上一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/10/6b6f6e13-d255-47ac-abe1-37232c36d0ce.png?resizew=374)
(1)求证:当
为
的中点时,平面
平面
;
(2)是否存在一点
,使平面
与平面
所成的锐二面角为
,若存在,求
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d47ad7ef0a17747fc54fe058bcb8d1a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51e231505648333857565accb0c3c898.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0468237bbc0d3df77435d98b817c10c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5164a3cc47e266446d49127e2ef10c37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/10/6b6f6e13-d255-47ac-abe1-37232c36d0ce.png?resizew=374)
(1)求证:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ac48b9ac8efbf41d6ab5242d247bd89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)是否存在一点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10ca5b5fd1031438de2d2dd59be8c348.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ed01d1ff5a7f21a68fb3a1e5c7f393e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/260200d547998bcac50a4a491382e7f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/505abdb4631fe10cdcdde3dc3d6aad32.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图,在直角梯形
中,
,
,
平面
,
,
.
(1)求证:
平面
;
(2)在直线BC上是否存在点M,使二面角
的大小为
?若存在,求出CM的长;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dceb5cc71fc50f20649f6b9535fd914.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4795ee1f96b430529934e2231b38885d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c41158715d94c6c9ffebdee957d2618.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6341d610ae81c6438772fbacfc2a1657.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0138efef1aa28c5b2b1063426ad87a4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20af148464904e21f4374cc8fb886fba.png)
(2)在直线BC上是否存在点M,使二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25a32a0fe258b74485e5b57891b4542c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
![](https://img.xkw.com/dksih/QBM/2015/12/30/1572407857020928/1572407863312384/STEM/9c1d09989ba148099cf69a09118e3ad5.png?resizew=290)
您最近一年使用:0次