如图1,在等腰梯形
中,
分别是
的中点,
,
,将
沿着
折起,使得点
与点
重合,平面
平面
,如图2.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/e0ad0bd0-a3b8-4436-b03a-f5a69d2a5de6.png?resizew=357)
(1)当
时,证明:
平面
;
(2)若平面
与平面
夹角的余弦值为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54eb01dd383cde273a69b863f96528e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26b85dbac306107b711eaa66690330b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1016eca2e30c6c75ff2b6bdd63f7ea5.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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ac48b9ac8efbf41d6ab5242d247bd89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/e0ad0bd0-a3b8-4436-b03a-f5a69d2a5de6.png?resizew=357)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73b3cf0f585938ede9eca890a6eb326d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2597b5554284e275367c25529c6750f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8be7470f11eed5536f3baf65e3a125d.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8be7470f11eed5536f3baf65e3a125d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d83fb9ac8a18e78a4c56da79514b5ccb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
更新时间:2022-12-14 22:57:30
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,在直四棱柱
中,四边形
为梯形,
,
,点
在线段
上,且
为
的中点
.
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e516121599c9fcc528121c00afcf52fc.png)
平面
;
(2)若直线
与平面
所成角的大小为
,求平面
与平面
所成角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb00c5327825200bf9b1bde4401760b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a0c2acd925d51e6960c8b427a0b5a6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/17/f276bce4-f7f0-4920-92b1-868b33a5e2c9.png?resizew=177)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e516121599c9fcc528121c00afcf52fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ebb05874eb3353d754af24c9974273e.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15dc61d5de97b5a40be925b278ae494c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e5fa72f2878b476bc57f0df12d6555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589c878e789e07e33d65c8a18cf2c58a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bff3ccea5989c60e51e321af3f53f54.png)
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解答题-问答题
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适中
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解题方法
【推荐2】在正方体
中,E是棱
的中点,在棱
上是否存在一点F,使
平面
?证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b18d58b61d9460d6cb917ee2a3bdeab0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923189afc198d153c79059a827f63c87.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,在三棱柱
中,
,
,
,平面
平面ABC.
![](https://img.xkw.com/dksih/QBM/2022/2/18/2919062437019648/2927386613194752/STEM/2638cf1b-9d5e-4416-b3dd-d54dbcc47fc6.png?resizew=188)
(1)求证:
;
(2)若M是线段
的中点,N是线段
上一点,且
平面
,求四棱锥
与三棱柱
的体积之比.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d56e653a138322672e5c8b5d6db958c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e3c9e7c05de9838c0c5d762720d3ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c06154cae3bf7a8ce5a1e97a7380875.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0671b4776e142e17a79af5b3f0378ef7.png)
![](https://img.xkw.com/dksih/QBM/2022/2/18/2919062437019648/2927386613194752/STEM/2638cf1b-9d5e-4416-b3dd-d54dbcc47fc6.png?resizew=188)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a28c816a483692b63e228cee6e8ac57.png)
(2)若M是线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eaa5e336f830a3e5cd60ff7a756f3ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/732b99eec725448839b6e7b42798970b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
您最近一年使用:0次
解答题-证明题
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解题方法
【推荐2】如图,正方形ABED的边长为1,AC=BC,平面ABED⊥平面ABC,直线CE与平面ABC所成角的正切值为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/31/275d8f76-7259-4904-a89c-953baf87b785.png?resizew=148)
(1)若G,F分别是EC,BD的中点,求证:
平面ABC;
(2)求证:平面BCD⊥平面ACD.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/31/275d8f76-7259-4904-a89c-953baf87b785.png?resizew=148)
(1)若G,F分别是EC,BD的中点,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf60ad9db3411f35704fa88d86bfef5a.png)
(2)求证:平面BCD⊥平面ACD.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图甲,在四边形
中,
,
,
,
.将
与
沿
,
同侧折起,连接
得到图乙的空间几何体
.点
为线段
上的一点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/b9227333-dcb0-42dc-9432-596e6fd79f28.png?resizew=316)
(1)若
,证明:
;
(2)若
,
,平面
与平面
所成锐二面角的正切值为8,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7286d20c833e8048aed515f45dfd842c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7521601ac1fbc4a52d4fe44be9c8e88c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15bd5bf70253169de1becbeef5a00eaf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eff00441c41fc516c37876d266fcbc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/535770901287f244911b42412533d4a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/b9227333-dcb0-42dc-9432-596e6fd79f28.png?resizew=316)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce0d7095ddd69d6ceaf1065b1bc2c79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5322a78b02c2bc387ea7dce3e9461974.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5519c1efed9b34725446c2ee488ab3c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5922fde863f09b2dc5116e770f6299a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf6c7b71d5689f613d106a141b548434.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,在四面体
中,
,平面
平面
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94117be6898f465b621b00d996cea62a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/5/56ffbb5b-b88f-4c45-ba34-22b9b5c428c2.png?resizew=168)
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a916d31a199e250556fb7478d9f57f7.png)
(2)若二面角
的余弦值为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a351136b18bc7d3bd5122332772ab23b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68e588d344b5ea3f8069ea54a631db20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94117be6898f465b621b00d996cea62a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/5/56ffbb5b-b88f-4c45-ba34-22b9b5c428c2.png?resizew=168)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a916d31a199e250556fb7478d9f57f7.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b796bbaeb8450404c2d146283562006e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83303d3784492506fc44f2b4d6b07bc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b79dd200766db27fb90d6bd1992cf658.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
【推荐3】如图,在四棱锥
中,
底面
,
为直角,
,
,
、
分别为
、
的中点.
(1)证明:
平面
;
(2)设
,若平面
与平面
的夹角大于
,求
的取值范围.
![](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/2947ca8e0cdbeb4aab80ce9e7b63ba98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22ac5b6035f4dd5913d7c7444fce85ba.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36955c0abda2c3ab96f1d77dbb79145e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65277734669566578cbb7d690bb200fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4739afd7311501e948aa4e1e5c1cb17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e5fa72f2878b476bc57f0df12d6555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://img.xkw.com/dksih/QBM/2011/3/1/1570021264982016/1570021270470656/STEM/3e73636418dc4069bbe8e9a0c2aed8e2.png?resizew=274)
您最近一年使用:0次