如图1,梯形
中,
,过
分别作
,垂足分别为
,已知
,将梯形
沿
折起,得空间几何体
,如图2.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/15/33dd5448-4a02-4204-a31d-12ac94cc38d1.png?resizew=374)
(1)在图2中,若
,证明:
平面
.
(2)在图2中,若
,在线段
上求一点
,使
与平面
所成角的正弦值最大,并求出这个最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e52586ca2a3b783bc8092415e2d4bf6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b40d626dbb862ac3d45721ff5751731.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac491f44725f78c7fc276a76810f8c96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82773737609e65dea3c5c67099f1b10d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45de0916d8d18f2eb495e08e6bbc3016.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/535770901287f244911b42412533d4a9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/11/15/33dd5448-4a02-4204-a31d-12ac94cc38d1.png?resizew=374)
(1)在图2中,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e39b13d187b25461d85a3b8d10c7b678.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/369eb8ad56da7dc1cdb7c43762be4bee.png)
(2)在图2中,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7250d92ddfc54adf0c091590e4cdf2c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
更新时间:2023-10-24 09:21:50
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】三棱柱
的直观图及三视图(主视图和俯视图是正方形,左侧图是等腰直角三角形)如图,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2012/2/13/1570734397030400/1570734402379776/STEM/61b324465c6b473a84a058c937b0dba9.png?resizew=196)
![](https://img.xkw.com/dksih/QBM/2012/2/13/1570734397030400/1570734402379776/STEM/4c713b4a92e74b87bb304917e04c6d1e.png?resizew=204)
(1)求证:
平面
;
(2)求证:
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ede6a60cad0e0b58e1549fda6e085719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://img.xkw.com/dksih/QBM/2012/2/13/1570734397030400/1570734402379776/STEM/61b324465c6b473a84a058c937b0dba9.png?resizew=196)
![](https://img.xkw.com/dksih/QBM/2012/2/13/1570734397030400/1570734402379776/STEM/4c713b4a92e74b87bb304917e04c6d1e.png?resizew=204)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0f31c75b24e9f46ac73118fde73d143.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/361ba681e1c611ef91f4374374062914.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52e2a9dfb75f36fe375d1693add819dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/361ba681e1c611ef91f4374374062914.png)
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解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图,在四棱锥
中,平面
平面
,
,
,
,
,
,
,
分别为
,
的中点,
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/3a8d847e-3074-4285-a6e5-29b01fe29efa.png?resizew=145)
(1)求证:
,
,
,
四点在同一球面上,并说明球心及半径;
(2)画出平面
与平面
的交线(不需要写画法).
(3)设平面
与平面
的交线为
,直线
与平面
所成角的正切值为
,求平面
与平面
所成的锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df5c044e1f89e113f1f4f63cf60c7518.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/62974d34de3a12418d6b700420afd1b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4795ee1f96b430529934e2231b38885d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5729dd997ea7e8cb4cef8b7165b36e00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/13/3a8d847e-3074-4285-a6e5-29b01fe29efa.png?resizew=145)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)画出平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(3)设平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e108d5c61e85e0741ec2c484fc5768.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ef4b918d022644e812c610a7308019.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
名校
【推荐3】如图,在长方体
中,点
、
分别在
、
上,且
,
.
平面
;
(2)设
,
,
,求平面
与平面
所成的锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.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/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4305d8d52fe2cc79c78129652e64bb62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fccb37728702288d4be7148301ab685.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d26d8a9d64ad3c8cba28840b41ed7837.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0d5a2cd05e4476fc72271e8fdb59a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f3e58edd1f900ca82bb2a3058293f52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b4cd2b33bd983a9ed6575b9de04a46a.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】如图,在正方体
中,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/28/c5bd959d-fdc0-46a9-b8e8-44b90a45e8b1.png?resizew=161)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/28/c5bd959d-fdc0-46a9-b8e8-44b90a45e8b1.png?resizew=161)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d67be899bc131ec1b9921ae9787c40d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b886daa3c9bb7153acd9f651f99eb2c1.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b886daa3c9bb7153acd9f651f99eb2c1.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,几何体
中,平面
平面ABC,
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/3/23/2942508286009344/2943028567359488/STEM/9f53c1dd67f9498092dea16e6902bc97.png?resizew=245)
(1)证明:
;
(2)若
,
,求直线DA与平面EAB所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bde1e200d1dd5ddc433c876c9d2f688c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9332278351ab92e03e984e9279dd06a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3a6dcaf9f9e9a940b4a16f7ec2fc2d.png)
![](https://img.xkw.com/dksih/QBM/2022/3/23/2942508286009344/2943028567359488/STEM/9f53c1dd67f9498092dea16e6902bc97.png?resizew=245)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd260fb9d772c122dcb1df52cbe38ab.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c776123acaded2ccf842d180b9f7741a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b547d886c528fa2c63016c217b8fb51.png)
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,在多面体
中,平面
平面
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/16/ee55d280-2694-4a53-9b85-dc10cb93c16c.png?resizew=200)
(1)求证:
;
(2)若四边形
为矩形,且
,求直线
与平面
所成角的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2a4e3f0349fa83dc2a0b7d798f04843.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/16/ee55d280-2694-4a53-9b85-dc10cb93c16c.png?resizew=200)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70c5fd65265f85df7d149d83d80d4e62.png)
(2)若四边形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd4b93d7abcfc4c3df48f03aa969c17f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/755b680b34589e9caa1920bf5a8d3258.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/422210c777ac0d625bbd81cc7601bf9b.png)
您最近一年使用:0次