如图,在正方体
中,E、F分别是
的中点.
![](https://img.xkw.com/dksih/QBM/2018/11/27/2084697935331328/2085504195239936/STEM/00f6a5b505c64c8790f15536e3c38f1e.png?resizew=207)
(1)证明:
;(2)证明:面
;
(3)设
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52b841b79b6fb860df88776738d6dd3a.png)
![](https://img.xkw.com/dksih/QBM/2018/11/27/2084697935331328/2085504195239936/STEM/00f6a5b505c64c8790f15536e3c38f1e.png?resizew=207)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53dd7905ef4b7e7f200476d6c205ff43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0946d63c06a45c8b68cc9c7b5fec599.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92535536bd3c2761724fd058427f95a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dc36aa92cc677ae1cd3c180daa1e8e7.png)
更新时间:2018-11-28 21:52:03
|
相似题推荐
【推荐1】如图,四边形
是矩形,
,
,
,
分别为
,
上的一点,且
,
,将矩形
卷成以
,
为母线的圆柱的半个侧面,且
,
分别为圆柱的上、下底面的直径.
![](https://img.xkw.com/dksih/QBM/2020/4/29/2451848467415040/2452628700954624/STEM/18ff2ddf035d48a9a495bf80ea165a15.png?resizew=125)
![](https://img.xkw.com/dksih/QBM/2020/4/29/2451848467415040/2452628700954624/STEM/5ab82912d22642d8a06f2689555720a8.png?resizew=109)
(1)求证:平面
平面
;
(2)求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fcd91638905c88f16d61963787eb0ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc11331a7b2d2619b40ee6d34c3bd620.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/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bcab18779e8a919934ae3e6e252e570.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5b1059547004671f270b1612ca27596.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/2020/4/29/2451848467415040/2452628700954624/STEM/18ff2ddf035d48a9a495bf80ea165a15.png?resizew=125)
![](https://img.xkw.com/dksih/QBM/2020/4/29/2451848467415040/2452628700954624/STEM/5ab82912d22642d8a06f2689555720a8.png?resizew=109)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9367449a5847eade07e69f4feddcb027.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b312dab930cbbb9a4bb1a99f044dab73.png)
(2)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75334faa2d3703b41bd1149895d7db94.png)
您最近一年使用:0次
【推荐2】亭子是一种中国传统建筑,多建于园林,人们在欣赏美景的同时也能在亭子里休息、避雨、乘凉(如图1).假设我们把亭子看成由一个圆锥
与一个圆柱
构成的几何体
(如图2,其中
,
,
三点共线).一般地,设圆锥
中母线与底面所成角的大小为
,当
时,方能满足建筑要求.已知圆锥高为1.6米,底面半径为2.4米.圆柱高为3米,底面半径为2米.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/26/99f35146-06e1-471f-8ece-87c90df79a75.png?resizew=301)
(1)求几何体
的体积;
(2)如图2,设
为圆柱底面半圆弧
的三等分点,求圆柱母线
和圆锥母线
所在异面直线所成角的正切值,并判断该亭子是否满足建筑要求.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4c5e80e1782eac5c106245682a9aa82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/192f4f9446c954a291f779d963f90257.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4c5e80e1782eac5c106245682a9aa82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38420cd107c7c6969663dc8bbae5edf1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/26/99f35146-06e1-471f-8ece-87c90df79a75.png?resizew=301)
(1)求几何体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0047f659c182291c84c224df6b5e993f.png)
(2)如图2,设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.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1】如图1,在直角梯形
中,E,F分别为
的三等分点,
,
,
,
,若沿着
,
折叠使得点A和点B重合,如图2所示,连结
,
.
![](https://img.xkw.com/dksih/QBM/2020/4/5/2435070618624000/2435813305548800/STEM/aac7f493e38f4191bccfb03c4366d450.png?resizew=286)
(1)求证:平面
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a200fc6444157edf072e9557d1ca777.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3688e3f493ae13a232df7cea574dae17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e36329f5e0979f5ee776ac5d06327.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21037e170bdbb322558e79c40c00b454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8e5f736b1195fef1d2d300168a795f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/2020/4/5/2435070618624000/2435813305548800/STEM/aac7f493e38f4191bccfb03c4366d450.png?resizew=286)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35c9529795ba241d68e1c4ce912b4334.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e6fb850d752d4527638f4df8ae71972.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】如图所示,用平面
表示圆柱的轴截面,
是圆柱底面的直径,
为底面圆心,
为母线
的中点,已知
为一条母线,且
.
(1)求证:平面
平面
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e07956720a50ff238c0766a5d58d00e2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/19/6ae32c15-3cd0-4881-a763-c67b4b986afe.png?resizew=180)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d66cdf7f987bb08a83b732a071ac2ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc28d80236679dacffd255cf64f1384.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b43cbc92b5f5c26c7f70b52b27616a81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9cd1ad6b8eac07253212dc6ec1168b96.png)
您最近一年使用:0次
【推荐1】如图,在正三棱柱
中,已知
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2023/8/22/3308359427948544/3309301135204352/STEM/d474b0642d494d92a76fb68b7822c737.png?resizew=141)
(1)求直线
与
所成角的正切值
(2)求证:平面
平面
,并求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92105835f8075cb75dff244e908370b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2023/8/22/3308359427948544/3309301135204352/STEM/d474b0642d494d92a76fb68b7822c737.png?resizew=141)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69a7bcc1efb8a2ff57d64b6d057da463.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa046f0b820bd6c237ae6db5669fe13a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc7e774e4ae40c23bf4ceed179230ca.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】在四棱锥
中,底面
为平行四边形,平面
平面
,
是边长为4的等边三角形,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/6aed97a2-b07a-4076-bea2-c3db993d79a7.png?resizew=223)
(1)求证:
;
(2)若直线
与平面
所成角的正弦值为
,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/94aad4c2109f60fcbf5488a545b16c6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94aad4c2109f60fcbf5488a545b16c6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f2c4814b1b841de5e16fc9298c3d40b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da48240e7fc3248f773ac1500c15ec14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bf64643144ce16930bd20cb438b999a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/6aed97a2-b07a-4076-bea2-c3db993d79a7.png?resizew=223)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1caa9333a47ad4c0dff7bb02fc89cfc.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ed24aeda4260685f4e1bd6b78a8ff25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.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,在三棱锥
中,
是
外接圆的直径,
垂直于圆所在的平面,
、
分别是棱
、
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/c14fdcd7-1a99-4217-9776-b8c39c1345fb.png?resizew=136)
(1)求证:
平面
;
(2)若二面角
为
,
,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/1/c14fdcd7-1a99-4217-9776-b8c39c1345fb.png?resizew=136)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51e231505648333857565accb0c3c898.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3304d151a8d42f932fbfb96f06bd9b69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
您最近一年使用:0次