已知梯形ABCD和矩形CDEF.在平面图形中,
,
.现将矩形CDEF沿CD进行如图所示的翻折,M为AE的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/8b2f8f85-1015-4725-acb0-32dae2cdad44.png?resizew=345)
(1)设N是BC的中点,求证:
平面CDEF;
(2)在翻折的过程中,当二面角A-CD-E的大小为
时,求直线BM与平面BCE所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b0bba92628a9b45cbba7721fc7e7722.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7dac702fe64edf1bc265da4b98cf2a0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/8b2f8f85-1015-4725-acb0-32dae2cdad44.png?resizew=345)
(1)设N是BC的中点,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7592c4f01c8e06c7ee90df5b9413a9f5.png)
(2)在翻折的过程中,当二面角A-CD-E的大小为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0211da37e92f915e781691296578ba0.png)
2022·黑龙江佳木斯·三模 查看更多[4]
黑龙江省佳木斯市第一中学2022届高三第三次模拟数学(理)试题(已下线)考向28利用空间向量求空间角(重点)(已下线)模拟卷02黑龙江省绥化市肇东市第四中学校2022-2023学年高三上学期期末数学试题
更新时间:2022-09-20 11:09:48
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,平面
平面
,四边形
为矩形,
和
均为等腰直角三角形,且
.
![](https://img.xkw.com/dksih/QBM/2021/10/24/2836443365507072/2838620690685952/STEM/666fa56bf29c492886ea5d466a5bca9c.png?resizew=187)
(1)求证:平面
平面
;
(2)若点
为线段
上任意一点,求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5ec3f44cd7f4689920e5df628177737.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/004104bafb5f30338123d4ea2b7fedde.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52c5fd1c0e29b240c0b8906ca9054a46.png)
![](https://img.xkw.com/dksih/QBM/2021/10/24/2836443365507072/2838620690685952/STEM/666fa56bf29c492886ea5d466a5bca9c.png?resizew=187)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39282bdf319f30d7bc261e2e3ab3b1e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/735056c174e8dd7906257a2a50a962a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e60db93cd34a54c98da9ff9782656c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.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,在四棱锥
中,
,
,
,AB=AC=2,AE=ED=1.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/1b66493c-c26b-4f22-87d8-9c5efe2a5712.png?resizew=171)
(1)若F为AC中点,G为AB中点,
,求证:
平面BCD;
(2)若平面
平面ABC,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f9045e6cd575bbe76c89ef6ef852fd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7bd02e0adeae92ba9526261b1baf797.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/032b3e422eeb39cf649dffc9934a7cf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/1b66493c-c26b-4f22-87d8-9c5efe2a5712.png?resizew=171)
(1)若F为AC中点,G为AB中点,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c97a7fab5d1550e2fef66772cc985fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5d62dcf1c173fe35595dfed43f9c87.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31effd1d3f7ce1f6e57be80c7f3af4ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b9fac14c8330781420fa076b2e04e77.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1】已知四棱锥
中,
底面
,底面
为平行四边形,
,
,
为
的中点,且三棱锥
的体积为
.
![](https://img.xkw.com/dksih/QBM/2021/5/23/2727165958496256/2727250111946752/STEM/7dc99880-ced0-4834-928d-934ea06d4062.png?resizew=237)
(1)求证:平面
平面
;
(2)设点
为四棱锥
外接球的球心,求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e075468e7fb0bf30229aec01a7205977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e7b6d04f024ca05cdfacc8ce9137c15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/790c0a17ee2d7181ee95da741694bd1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5040d31e784398842b04ed7dd0aacc10.png)
![](https://img.xkw.com/dksih/QBM/2021/5/23/2727165958496256/2727250111946752/STEM/7dc99880-ced0-4834-928d-934ea06d4062.png?resizew=237)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392469b357b12b998528499929366c02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2a355389fc797dbe23960c55c18df83.png)
(2)设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5c6e364087f8a4780a48a7e745a6a14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7e3ad4c3c900cc3460067d95d0abbd9.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,直角梯形ABCD与等腰直角三角形ABE所在的平面相互垂直,
,
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bbf6796681347c82b07c4dd30800f1a.png)
![](https://img.xkw.com/dksih/QBM/2022/6/1/2991846900891648/2995521393573888/STEM/49646d89-b74c-45fb-82cf-845b46eb57e0.png?resizew=271)
(1)求证:
;
(2)求锐二面角
的余弦值;
(3)线段EA上是否存在点F,使
平面
?若存在,求
的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbf9194bd849f2648721a4d0222a375e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bbf6796681347c82b07c4dd30800f1a.png)
![](https://img.xkw.com/dksih/QBM/2022/6/1/2991846900891648/2995521393573888/STEM/49646d89-b74c-45fb-82cf-845b46eb57e0.png?resizew=271)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9874eca4abea481fa84eb772a920f9c7.png)
(2)求锐二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/445b51117626fbd3373e32acc514c64b.png)
(3)线段EA上是否存在点F,使
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/871221c3eaabb6d9b030ce91c7139709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/128c69eb81dae89c6989d06d20925ad2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c38757c4b09eddb4b0f3c472f4d90626.png)
您最近一年使用:0次