在四棱锥
中,底面
是平行四边形,
平面
,点
,
分别为
,
的中点,且
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/4/8ea93558-85f5-4ccf-9a6b-55f5e01f40c2.png?resizew=167)
(1)证明:
平面
;
(2)求直线
与平面
所成角的余弦值.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.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/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3b10835116b9b777a666b438c907b49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e240a6378adf6d23ebf9cc710c9bd6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/4/8ea93558-85f5-4ccf-9a6b-55f5e01f40c2.png?resizew=167)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02438f0423acd0ff2dfa5ffb6abf143f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
更新时间:2019-09-19 18:09:51
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,已知直角梯形
与
,
,
,
,
,
,G是线段
上一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/13/221d633a-7ea2-4d20-a821-0ce3d0a16a0e.png?resizew=155)
(1)求证:
平面
;
(2)若平面
上平面
,设平面
与平面
所成角为
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e17cc589a40a0a4c4319ebdfa866c69c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a47dcb24ffe20e8153e0d113ff8bee3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ad3bf04b68238517703cf2f0f712aed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9060f03b9ee41d70d135b1e1a8902ce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5acb763021bf166ca719d07223591d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/13/221d633a-7ea2-4d20-a821-0ce3d0a16a0e.png?resizew=155)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11d27ff0b39832f094ec51e28721d739.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9efe66d99f813c6b1387392186822bb.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ecc1cb55a57dde481f8dd07ab150676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d666dd3308604685e59f4ca22663b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20af148464904e21f4374cc8fb886fba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefd06c239145a2b6ae87a955aa51414.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】在四棱柱
中,已知底面ABCD是菱形,
平面ABCD,M、N分别是棱
、
的中点
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/7bc6777e-a4a7-4fbd-9dc9-c48c582f2580.png?resizew=159)
证明:
平面DMN;
证明:平面
平面在
D.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd694ad3a4733c7c84aaa7946aeea4de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/326a3339175592bd1e793a9054d57fe5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3225b8916372c7e0e4d7b71b26571e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/823e998089a7f79b713d3862ab2e81aa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/7bc6777e-a4a7-4fbd-9dc9-c48c582f2580.png?resizew=159)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4141b26d2c32655003494a91ad6331b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de411e207364bd4bdc34bc925d27f869.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65863c1abad833b79c303bfca24f535c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a38f7b7c4ac9e79fb32b02bd26acefa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae4779134c28e991b5395939a4de8321.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
真题
解题方法
【推荐1】如图,在三棱锥
中,
,
,
,点
在平面
内的射影
在
上.
(1)求直线
与平面
所成的角的大小;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6df9b574c6b6a4c878bf425d4fa31d66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64e68018750dcdcb6a346761c96a45cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc63b945d37ff1fc7c4df312c3c23fd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e820aec9c1a975242fe6d76408a9cde8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/399885fe-1d82-461d-a195-831eee9d8f3f.png?resizew=220)
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
为等腰梯形,且满足
,
,
平面
.
![](https://img.xkw.com/dksih/QBM/2019/6/7/2220505330057216/2221214775066624/STEM/05d2a76779904de19d733a389e64e448.png?resizew=144)
(1)求证:平面
平面
;
(2)若
,求直线
与平面
所成角的正弦值.
![](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/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/555e29e445c95ddb514840f63fbb1d12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://img.xkw.com/dksih/QBM/2019/6/7/2220505330057216/2221214775066624/STEM/05d2a76779904de19d733a389e64e448.png?resizew=144)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829f9180ddd9aa1a0ee0dc520f4e0b5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
您最近一年使用:0次