在如图所示的几何体中,
平面
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6785c7c85a503531649f9c9b4cbfcf04.png)
,
是
的中点,
,
.
(1)证明:
平面
;
(2)求二面角
的大小的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6785c7c85a503531649f9c9b4cbfcf04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7ad3a578f403b9e6b97fa2dc955fc11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a91d85e795f17c90b2e8c0d9f7ff2e6.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40f44f2b2f82a9126223138972850aa2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b10f890a5f9bc9140286f8326398d16.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/9/9ecee84f-3773-491c-a393-6a39459f242f.png?resizew=121)
2014·湖南长沙·二模 查看更多[1]
(已下线)2014届湖南省长沙市高考二模理科数学试卷
更新时间:2016-12-03 01:12:21
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】在四棱锥
中,平面
平面
,
是等腰直角三角形,
,
,
,
,
是
的中点,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2021/8/14/2785820825075712/2819334574292992/STEM/573fc3d45ec04963a21f71f8e2716e31.png?resizew=253)
(1)求证:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62974d34de3a12418d6b700420afd1b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/625bca170fed3fbdc1441b3c0df4a6bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e918b70b02a73685e3c536c7f380e2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/2021/8/14/2785820825075712/2819334574292992/STEM/573fc3d45ec04963a21f71f8e2716e31.png?resizew=253)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96b8c2721ada247b03f41f328539b301.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f086a71081b17c68aff8c7249a80754e.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,圆台
的轴截面为四边形
,其中
,P为圆
上异于
,
的点,M为PB的中点.
平面
.
(2)当三棱锥
的体积取得最大值
时,平面
平面
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae0a4f38420bb9215dbc9c875b755838.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bea124cef7ab3fd8069243e9894d1c59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d134433600df75f2a5d0f35deb2cac90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b755220de0b3b266130b16503581ed96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a55abeb09dbf9caf131d1f7117e2d02a.png)
(2)当三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6db196b5e16207b134234e498213ff0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18483c9c195ecd922772527fa85c0fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ed615421106fda56cda4b5735dae578.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46c449afefb153648f083271911d4051.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ba75e8b878d9bbf2a50f946c232187a.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,在多面体ABCDPQ中,四边形ABCD为菱形,
,
,
,平面
平面ABCD,
平面ABCD,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/29/585a1d1b-edbd-4526-858c-f0a5e1e81d0e.png?resizew=156)
(1)证明:
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff5a86745bfe1dfe7bc2683811210330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1328e05d150f86dbe18656662eaa8f6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/230773e239052ba228224f9a81cbb2b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a036c917cd2d5af487d1145782b7f07.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/29/585a1d1b-edbd-4526-858c-f0a5e1e81d0e.png?resizew=156)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b182ff664d8ed9d0c518dbbf98ef10f.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbe4b104afcade753f8eb811db759c92.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】在正方体
中,求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98e0254c84e44728749b34c08c28ab1e.png)
您最近一年使用:0次