如图,在四棱锥
中,
,
,
,
分别为棱
,
的中点,
,
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/7fbb3f05-f304-4937-8db9-c83ec288d998.png?resizew=162)
(1)证明:平面
平面
.
(2)若四棱锥
的高为3,求该四棱锥的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f79863ffcfa63117ca6741b20a48e69.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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eca7e1a727ba332984ad857b3d25344d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/519d3cbe962154438e43a23b0d9eda2f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/7fbb3f05-f304-4937-8db9-c83ec288d998.png?resizew=162)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b711c453131b5420cbade7e0e451b908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
(2)若四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
更新时间:2020-03-11 21:23:25
|
相似题推荐
解答题-问答题
|
较易
(0.85)
名校
解题方法
【推荐1】如图,四棱锥
的底边
是正方形,点
、点
分别是线段
、
的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/c40e7fff-9838-45c0-91db-0bfd4fa21776.png?resizew=191)
(1)证明:
平面
;
(2)若
是四棱锥
的高,求三棱锥
的体积.
![](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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e7b6d04f024ca05cdfacc8ce9137c15.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/c40e7fff-9838-45c0-91db-0bfd4fa21776.png?resizew=191)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de8a21df84cf292db93b937f4ea47bfe.png)
您最近一年使用:0次
解答题-证明题
|
较易
(0.85)
【推荐2】如图,四棱锥
的底面
是矩形,
平面
,
.
![](https://img.xkw.com/dksih/QBM/2022/7/15/3023254720167936/3026700605685760/STEM/35c7e430ebe44103b612d46bc45ef548.png?resizew=221)
(1)求证:
;
(2)求三棱锥
的体积;
(3)求平面
和平面
夹角的余弦值的大小.
![](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/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5ef03497414d454933f76684ee16970.png)
![](https://img.xkw.com/dksih/QBM/2022/7/15/3023254720167936/3026700605685760/STEM/35c7e430ebe44103b612d46bc45ef548.png?resizew=221)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/712f7375b4ede5f75c0d81870c0f86af.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b568ba5f8e290c966a4fcd4a46005c7.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
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解答题-证明题
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较易
(0.85)
解题方法
【推荐1】如图,已知点P为
所在平面外任一点,点D,E,F分别在射线
,
,
上,并且
.求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.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/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3e039746fc7495ed893b88c41323d4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0830cad1bd51a13a3673bf2cc5f906d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
您最近一年使用:0次
解答题-证明题
|
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(0.85)
解题方法
【推荐2】如图,在直三棱柱
中,侧面
为正方形,且
,点D、E分别为棱
的中点.
![](https://img.xkw.com/dksih/QBM/2021/3/22/2683162211942400/2690006149177344/STEM/d87e355cfaac46b59a45e5a949cb2dea.png?resizew=201)
(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/ee8b5a6dbcf05f572f83f51abf7d668c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/093278b91d6760b1f57fa26a1452bc30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82f3327964cfd3ad40d603b0ba7f6973.png)
![](https://img.xkw.com/dksih/QBM/2021/3/22/2683162211942400/2690006149177344/STEM/d87e355cfaac46b59a45e5a949cb2dea.png?resizew=201)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee8b5a6dbcf05f572f83f51abf7d668c.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea848cd2aa3a464618020475097949fc.png)
您最近一年使用:0次