如图,在直角梯形
中,
平面
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/3d31b6eb-ce9d-4ffc-bff0-0d5cd859cc47.png?resizew=219)
(1)求证:
;
(2)在线段
上是否存在点M,使平面
与平面
的夹角的大小为
?若存在,求出
的长;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e96cfbb567f89c1a05eb5462ab78041f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/117878cbd8c00f2aabcdf62b487e2dc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6341d610ae81c6438772fbacfc2a1657.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/26/3d31b6eb-ce9d-4ffc-bff0-0d5cd859cc47.png?resizew=219)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4d498c5bd6f0bc27ab2ebd2c003c666.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/398616fc3e4f7a7075a0c3630ecca2d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e8a20c1fc8a5620db5db3a74eb01201.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db54223bb3fc2fe2497213a4d1f94827.png)
更新时间:2022-12-23 19:07:46
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,ABCD为圆柱
的轴截面,P为底面半圆周上一点,E为PC中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/42982c46-1cf2-4077-aa83-a73e0946f055.jpg?resizew=169)
(1)求证:
;
(2)若
,求平面PAD与平面ABE所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cffa35373ec4e4684107b42adb7a5161.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d320f180419175d75eebc618cc458b39.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/42982c46-1cf2-4077-aa83-a73e0946f055.jpg?resizew=169)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09c94ff4614059e5e91ed304b150d886.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f35b3fcb8c06368e2775ffc416158ba.png)
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解题方法
【推荐2】如图,已知在三棱锥
中,
平面
,
,
,
分别为
,
,
的中点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/19/eaa12b23-bd4f-40db-bed3-4751fb1143ba.png?resizew=208)
(1)求证:
;
(2)设平面
与
交于点
,求证:
为
的中点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.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/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92a3680ec97ccbb82b6e1ff78ac10b7c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/19/eaa12b23-bd4f-40db-bed3-4751fb1143ba.png?resizew=208)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0063f3f48e49f2970ec7f097567cef5.png)
(2)设平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/611f100dcfa7803db6eb233e2e7f2dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
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解答题-证明题
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适中
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【推荐3】如图,正方形
的边长为
,
是
的中点,
是
上的点,将
及
分别沿
和
折起,使
、
重合于
,且二面角
为直二面角.
(1)求证:
;
(2)求
与面
所成的角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5a0be7cbc1bd1f70b078111ed2a3f9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57831b59ea828a088ed9daec8babb774.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9eee50e904fed4ad9c6292bec0b08a8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35391a4e1e64e30751e1fe8102044d1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e61af2ac959eee2f4fd476eff114cb4.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddbb52f9b226b1db3f6f9f055948bd38.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/678b28fddb166d90878d24d6e5481080.png)
![](https://img.xkw.com/dksih/QBM/2010/7/7/1569782356746240/1569782361997312/STEM/7abf9d9e-7752-41f9-a378-dad0be30fb75.png?resizew=374)
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解答题-问答题
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(0.65)
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解题方法
【推荐1】如图,在圆锥
中,
的内接
为等边三角形,
,且圆锥的侧面展开图恰好为半圆.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/15/4d01a870-469a-4995-8e97-10d83ce2db30.png?resizew=157)
(1)证明:
;
(2)点
是底面
上的一个动点,
,求二面角
余弦值的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18e5ef91fb27dd684a27ae7f1993cfba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9774f83067ed956a551bc41adcce0469.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/15/4d01a870-469a-4995-8e97-10d83ce2db30.png?resizew=157)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e7c18f9db65fcd840b39d7bbd3028c.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d97cdc586744d208b6f69c9813af977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09cb74a4c5de601b57b2cb45ecd1cf5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/486aa57b8d51f4bafedf8b31ed0b6452.png)
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【推荐2】如图,正三棱锥
中,E,F分别是侧棱AC,AD的中点,连接EF.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/ecf5dda8-6390-4ae7-958f-98e97b0aa0cf.png?resizew=152)
(1)判断AB与EF的位置关系,说明理由;
(2)若
,
,求平面BCD与平面BEF所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/9/ecf5dda8-6390-4ae7-958f-98e97b0aa0cf.png?resizew=152)
(1)判断AB与EF的位置关系,说明理由;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
您最近一年使用:0次
解答题-证明题
|
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(0.65)
名校
解题方法
【推荐1】如图1,在边长为4的菱形
中,
,
于点
,将
沿
折起到
的位置,使
,如图2.
(1)求证:
平面
;
(2)判断在线段
上是否存在一点
,使平面
平面
?若存在,求出
的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f945a69cf7e8213e50622125cde652f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c38dfd14dde969702dff97ef2270f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3aa2a83fed9bf4cb09d84a980452e346.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967bd1d8bd38f6be7931eef41db106.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/29/947b4e1d-148e-4a69-bffb-7734ca07495f.png?resizew=329)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4525c00ed908bed8ba8d353e747a858.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
(2)判断在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/339128336cb6905dc8537e58f55ad3f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e14d78cfdef4aa7d877607e7fc35b3e3.png)
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【推荐2】如图,等腰梯形
中,
,现以
为折痕把
折起,使点
到达点
的位置,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/21/b285b1ca-8d3e-4a86-8cfe-53386684e916.png?resizew=358)
(1)证明:平面
平面
;
(2)
为
上的一点,若平面
与平面
的夹角的余弦值为
,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87f7e75bd54238cc668777aae4024919.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b44f4120c94cb7176dc31fcac387b32e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/21/b285b1ca-8d3e-4a86-8cfe-53386684e916.png?resizew=358)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af68a7bf0da4f7c6f739d2e2461ad9b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9868f77d5ab5073b6145f1c6d272122e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af68a7bf0da4f7c6f739d2e2461ad9b7.png)
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