如图,在四面体
中,
,
分别是
的中点.
;
(2)在
上能否找到一点
,使
平面
?若存在,请求出
的值,若不存在,请说明理由;
(3)若平面
平面
,且
,求直线
与平面
所成角的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3931333820859378ea6723ff3075189.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f80f50d21f51d27f11d360393b5b696b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b918a3c3c4ee032d291c9b817bd2bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cca04b2a2b61d62a809776670a60c09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfc1f76257275ab4b04f9bc913535670.png)
(2)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9d32e76582bf550593fdef53e081225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/524eb6b7cb4c5736285af33101a78789.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee7e6f1b753b73381b71eb5f8cc7da42.png)
(3)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d6e65c7f741e0ff37244cded47605e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e66ccb8f442161808545bc033b0ef7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
23-24高一下·浙江宁波·期中 查看更多[5]
浙江省宁波市北仑中学2023-2024学年高一下学期期中考试数学试题(已下线)第八章 本章综合--方法提升应用【第三练】“上好三节课,做好三套题“高中数学素养晋级之路(已下线)第六章立体几何初步章末二十种常考题型归类(2)-【帮课堂】(北师大版2019必修第二册)江苏省苏州市相城区陆慕高级中学2023-2024学年高一下学期5月月考数学试题湖南省邵东市第一中学2023-2024学年高一下学期第三次月考数学试题
更新时间:2024-05-08 16:35:23
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,四边形
为矩形,
,
,
为线段
上的动点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/fec78456-6abd-47c4-abc8-5fb3827fa518.png?resizew=168)
(1)若
为线段
的中点,求证:
平面
;
(2)若三棱锥
的体积记为
,四棱锥
的体积记为
,当
时,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49da41170a32e14b6b09d7031e7c1a62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fad13c99af5791d396fe3137727c9a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd17a66a2af938c89e46f22e4d893b1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/fec78456-6abd-47c4-abc8-5fb3827fa518.png?resizew=168)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd17a66a2af938c89e46f22e4d893b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b6053e396df2cd152e1329fce766d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53bdef2e7a7929ad6190302ab44c46c0.png)
(2)若三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bfc470aaef9ba9870a7f9264feee39c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7a20cdabc328d6bd9b69c97ed892ffc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb77e46b82b1edbf990e0d0577381932.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,在三棱柱
中,
底面
,且
,
是
的中点.
(
)求证:
平面
.
(
)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d25e8fc3dda4f8b45491514b6e22a962.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce9bfff622109f8992b2ed175960dcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5888bec948373f3854258ad80171073d.png)
![](https://img.xkw.com/dksih/QBM/2017/11/3/1809205177556992/1810592225484800/STEM/f34d35bf4adc496a93f3cd8cb615568d.png?resizew=185)
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】在四棱锥
中,
,
,
平面
,E为
的中点,M为
的中点,
.
![](https://img.xkw.com/dksih/QBM/2021/1/30/2647169320935424/2649294980972544/STEM/17179fa1ce934665a25cf9a84e6d340d.png?resizew=168)
(1)求证:
平面
;
(2)取
的中点F,证明:
平面
;
(3)在(2)的条件下,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37444a4da006d26dd252bee7c6cecf01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6853d227df9b14f4cbd5560f913e54a4.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/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e2942390d02efaff57473d103f7950a.png)
![](https://img.xkw.com/dksih/QBM/2021/1/30/2647169320935424/2649294980972544/STEM/17179fa1ce934665a25cf9a84e6d340d.png?resizew=168)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b766876252d16f2e331ef2893d45cf04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)取
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f1897a7e856b42f8cee0f286ad913d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
(3)在(2)的条件下,求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f726924c16c769a012d7a111f81e44e7.png)
您最近一年使用:0次
【推荐2】在如图所示的几何体中,四边形
是正方形,
平面
分别为
的中点,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2881f2694ece9ec5206616fd723725f.png)
(1)求证:平面
平面
;
(2)求三棱锥
与四棱锥
的体积之比.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39967d6f3aed6ce7b6643787795d451d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0e76a032a7db10381086fd3fb3cb493.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69ce1d402d300dd79718f31750ed4536.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2881f2694ece9ec5206616fd723725f.png)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5394d00a80a5900d7fd7d9961868bd22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18655577ebc6a3c7ea22de29b841add7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a4b8b69b419c557ba61a2bdfaf4066.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/5/b357e0ed-e30b-4ba0-abd0-b2922a224560.png?resizew=174)
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1,在平行四边形
中,
,
,
,
,
分别为
,
的中点,现把平行四边形
沿折起如图2所示,连接
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/280e6228-7990-4679-9d9d-7e479f4c3b71.png?resizew=408)
(1)求证:
;
(2)若
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/883732ae71bfed76e07732ec709f4653.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a9f99fb3252a4b3b7a62e8a675ddce9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92535536bd3c2761724fd058427f95a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/883732ae71bfed76e07732ec709f4653.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa6cb992b6faad4744f85d73a3b76dd5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a56f2e56229a722d1f40d74d3967a3d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/280e6228-7990-4679-9d9d-7e479f4c3b71.png?resizew=408)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82c2b3adb41e8965f553da2e5086a751.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a677b42f8b427b21924a559b90141d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c44507c93f6180afd1697d2fa5a5c741.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,四棱锥
中,四边形
为平行四边形,
,
,
,
,点
在线段
上,
,点
在线段
,
.
![](https://img.xkw.com/dksih/QBM/2020/6/2/2476064771178496/2476804432912384/STEM/f0392dca-5cf3-48c0-829b-9c5580398d20.png?resizew=229)
(1)证明:
平面
;
(2)若平面
平面
,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/26d4e574c9d139615d991a168cfbf63b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d5a2cd05e4476fc72271e8fdb59a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdd0e56b76af80bc914d27a0e5f18568.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f44447c0867e6ba50c960f7b5bee7036.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5c89fa0b634202607a2de0815aabbe7.png)
![](https://img.xkw.com/dksih/QBM/2020/6/2/2476064771178496/2476804432912384/STEM/f0392dca-5cf3-48c0-829b-9c5580398d20.png?resizew=229)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac480d8d9d7821b62a603cf5cfda236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a4613db540c9cb6a9d7e963bf89c2a8.png)
(2)若平面
![](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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a4613db540c9cb6a9d7e963bf89c2a8.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:在多面体
中,四边形
是正方形,
平面
,
,
,点
为棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/17/1685a025-4396-4fd1-97c6-8a1694df5b01.png?resizew=197)
(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/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fa3c61d6c19e187b4b824b6f5610cdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3139e28714bfc3d5d875d78dd245d2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86d1125b47dec1c5e93143ee59ad862a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/17/1685a025-4396-4fd1-97c6-8a1694df5b01.png?resizew=197)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3143afe58004d0d90294803bb712429d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a681d311a864d38cf306a0c137cbcca.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28be1dbdf1c4df932252fe0029715f56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】一副三角板(
为等腰直角三角形,
,
为直角三角形,
)按如图所示的方式拼接,现将
沿
边折起,使得平面
平面
.
平面
;
(2)求直线
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98def34207985857afbb850e365bcc52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3d7090639341730951c1bc3c9b6164e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.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】已知直三棱柱
中,
,D是
中点,E是
中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/d447c38e-7587-4780-9ddf-8c396d01e571.png?resizew=132)
(1)求证:
平面
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/d447c38e-7587-4780-9ddf-8c396d01e571.png?resizew=132)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e168672b47d7e64dc1b404f8882c7dcf.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9539f8fb13345b449274b67bbda995db.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,
和
都是边长为2的正三角形,且它们所在平面互相垂直.
平面
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/df4e22f1-ad4d-4129-a16c-ec8ecc0deb09.png?resizew=146)
(1)设P是
的中点,证明:AP
平面
.
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b506b0941433a6a5d5387d0ec95596ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e18f38545fb6d8ba32c993f60dc9a774.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/14/df4e22f1-ad4d-4129-a16c-ec8ecc0deb09.png?resizew=146)
(1)设P是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/306681bd5aaa51e9c63ab3002e23dec5.png)
您最近一年使用:0次