如图,在三棱柱
中,
,顶点
在底面
上的射影恰为点
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/478c1288-409d-43eb-b10d-52bf78a437de.png?resizew=180)
(1)求证:
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)在线段
上确定一点
,使
,并求出二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d76cef03e6b2d02024495a840ab451.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/478c1288-409d-43eb-b10d-52bf78a437de.png?resizew=180)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1c401f9dd333b36433b56d7aef1ffc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d1f2ff0805c573e3c1fc1720d4e531e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ee992e4455f983dcec7c98d0e51e194.png)
更新时间:2023-12-18 20:45:19
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】如图,在四棱锥
中,底面
是矩形,
平面
,
,
分别是
、
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/9/89e3ab31-8a91-4933-83da-370cac2fc88f.png?resizew=202)
(1)证明:
平面
;
(2)证明:
平面
;
(3)若
平面
,求四棱锥
的体积.
![](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/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b624742fe28db114e0554c6c87bff05c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cf9b288c48c73463a2f214f02b6952a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/9/89e3ab31-8a91-4933-83da-370cac2fc88f.png?resizew=202)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a5f445af1ae136773cb338920552ff2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c45fbffb9e2c7fa7c5006cde8da0cabe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd108b4303ba28bd8d1ad99380a9a621.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】如图,在三棱锥
中,
平面
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/178ab14efe42a4ecfcd981ab8d90cf91.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/19/ee8dcf2e-3265-4976-b3d3-a8b4227dc456.png?resizew=158)
(1)证明:平面
平面PAC.
(2)设棱AB,BC的中点分别E,D,点F为棱PA上一点,若△DEF为等腰直角三角形,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/178ab14efe42a4ecfcd981ab8d90cf91.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/19/ee8dcf2e-3265-4976-b3d3-a8b4227dc456.png?resizew=158)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
(2)设棱AB,BC的中点分别E,D,点F为棱PA上一点,若△DEF为等腰直角三角形,求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b38f9aff8586c09a94a4fa350af0bd65.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3】如图,在四棱锥
中,底面
是矩形,点E在棱
上(异于点P,C),平面
与棱
交于点F.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/e8631669-c661-46a9-85a9-f2321148faac.png?resizew=168)
(1)求证:
;
(2)若
,求证:平面
平面
.
![](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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/e8631669-c661-46a9-85a9-f2321148faac.png?resizew=168)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c91baecb97fadd4f8ab49e6effcbc04.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac559a1a89bfb16e1c44cdd7ad2f2bbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】如图,在直棱柱
中,
为
的中点,
为
的三等分点(靠近点
).
大小为
,求
;
(2)若点
在
上,且
平面
,求
的长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5c7011b32c1d08388eaada28617beec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e94b3e216febe049f89f821701dd8f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3afc5d7e5ff7cb785308c9b6d21e8478.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f220434c51562f59e302899804899954.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/881129039cb98be128af55ffa1d3b7dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06e322e0c87479bba874db9ae9ba36b5.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图所示,在四棱锥
中,底面
为直角梯形,
,
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2023/8/9/3299380787298304/3302057721905152/STEM/49edbe4b97d44cb4b12cbcd8e096acad.png?resizew=249)
(1)求证:平面
平面
;
(2)求平面
与平面
所成二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80c753cb1eb73fd8d136d00462970797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62c9a6255f54f395572a922c801aa490.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa6481beb14c81b1371fdcede025b5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b98d3a8a7488e6a47fe18242e92316c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a88c44f558705de3bcefcfc0ece96b8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75929268210da5976bc37d080da030dd.png)
![](https://img.xkw.com/dksih/QBM/2023/8/9/3299380787298304/3302057721905152/STEM/49edbe4b97d44cb4b12cbcd8e096acad.png?resizew=249)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5f0cfc1049f84a04c81bd213afb8d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.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,在平面五边形
中,
,且
,
,
,
,将
沿
折起,使点
到
的位置,且
,得到如图2所示的四棱锥
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/d6775aac-1a11-49d6-96cf-35730bc5a132.png?resizew=315)
(1)求证:
平面
;
(2)求平面
与平面
所成锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52bbb16f9380dd62d556480a3944be31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30b0393ce62b24aa5f9b740d4cc6743b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbddd2af3cfa527fb9e1bacda99c3a11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd860b63c3c48a6c7f4b165cc8ac935d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beb4eb567b07a033a572132d2b50735a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d631f45bc652539853f236952afa5bbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b459d1f3f6ff1bed5911663604f4e0b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efeadd146662b5d8fe14a424138ef751.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/d6775aac-1a11-49d6-96cf-35730bc5a132.png?resizew=315)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f95475bfc06e884754eb4a455c3f434e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01ff27eea7545bb06f9472f91290c54e.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9068f29d671d76d1e95ba3a4eaff5b96.png)
您最近一年使用:0次