如图,在棱长为
的正方体
中,
,
,
,
分别是
,
,
,
的中点.
![](https://img.xkw.com/dksih/QBM/2020/4/16/2442986122027008/2443557535170560/STEM/755424b4-0e27-4cd7-baef-8ae2fc3e32d7.png?resizew=203)
(1)求证:平面
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://img.xkw.com/dksih/QBM/2020/4/16/2442986122027008/2443557535170560/STEM/755424b4-0e27-4cd7-baef-8ae2fc3e32d7.png?resizew=203)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8340b26d59e59647f7b18af60bdd4001.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2443a94bed3d2b1f95c04ebd61ac134a.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2443a94bed3d2b1f95c04ebd61ac134a.png)
更新时间:2020-04-17 18:53:26
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图所示,在四棱锥
中,底面
为梯形,
,
为侧棱
的中点,且
,
.求证:
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/dc1bed9e7cd7aa41d0cb0f9fc1ec5eaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc11331a7b2d2619b40ee6d34c3bd620.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/544381069cb72bed5598ca5adc45ae26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/7/ea823bd2-28ec-4d7b-ab49-3fa1315354a7.png?resizew=161)
您最近一年使用:0次
【推荐2】如图所示长方形
,
,现沿
,
两道折痕进行折叠,
、
均与
垂直,
,成为如图所示立体图形
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/7f4cf4d1-3ae0-4a16-a7fb-4b19e938282f.png?resizew=261)
(1)若
,
,求证平面
平面
;
(2)在(1)的条件下,设
,请求出四面体
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b312dab930cbbb9a4bb1a99f044dab73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2cbc5784e07bf671a4c2563a980a12f.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a84d464a5d802bd0137e6135a9002f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/7f4cf4d1-3ae0-4a16-a7fb-4b19e938282f.png?resizew=261)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f6a1c26c5bef0793aded55a75a2d84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/226624e3444853e3cf92d8e11c829a90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad16260099de12b57de1e4e3e44acf53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)在(1)的条件下,设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c859a868a59655d831bbd18937c22b27.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图所示,四棱锥
中,
,
,
,点
是棱
的中点,平面
平面
,平面
过点
,
且交
于点
,直线
平面
.
![](https://img.xkw.com/dksih/QBM/2021/5/23/2727165178191872/2727281372340224/STEM/2e85eec75b06430a82fe19b84f678a29.png?resizew=175)
(1)求证:平面
平面
;
(2)若直线
与底面
所成的角为45°,求直线
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f48dce1a0d489d10e5eedd05d21237f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3384e2b63e4be03a8762b819499e669b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe1ff9bfc023b52681d99c5029f3ed3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/877582b5387278008d14fe5932622fe7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9428c4a6a25d360a036aaf0a92e40988.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://img.xkw.com/dksih/QBM/2021/5/23/2727165178191872/2727281372340224/STEM/2e85eec75b06430a82fe19b84f678a29.png?resizew=175)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fa807136194c18d3ac58902c67f9333.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d923a338dd2d2e29336b42574d38448.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2bc5e50b8dfa02601c70822252854a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.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2】如图,在棱长为3的正方体ABCD-A1B1C1D1中,A1E=CF=1.
![](https://img.xkw.com/dksih/QBM/2020/2/24/2406149702770688/2406645441994752/STEM/db861d214e9b4ab6ab1858256f6d4569.png?resizew=114)
(1)求两条异面直线AC1与BE所成角的余弦值;
(2)求直线BB1与平面BED1F所成角的正弦值.
![](https://img.xkw.com/dksih/QBM/2020/2/24/2406149702770688/2406645441994752/STEM/db861d214e9b4ab6ab1858256f6d4569.png?resizew=114)
(1)求两条异面直线AC1与BE所成角的余弦值;
(2)求直线BB1与平面BED1F所成角的正弦值.
您最近一年使用:0次