如图,正方形
和四边形
所在平面互相垂直,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2016/3/7/1572523181506560/1572523187757056/STEM/7f7d35ead06444b5a97360b70f54337d.png)
(1)求证:
平面
;
(2)求证:
平面
;
(3)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34b0c4c783dd55685bd3e88bb31c6696.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bcc5e0709048d84ea1b0df0e4a1064b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ac19d4472be244b100f9239d036c8a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d94bbd04bbe142e2bb2a2d836a198325.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c41570cf4119bd2bb99857aeb656084.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/310d564ca2e2a53b2dad45836fa77ddb.png)
![](https://img.xkw.com/dksih/QBM/2016/3/7/1572523181506560/1572523187757056/STEM/7f7d35ead06444b5a97360b70f54337d.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2229bfd3ca52c4ba5eb9bfd691e703e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d2eb50b211620dbee09bc517dadffa1.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d03716ca46b8fb7cb42d8b2a6f75ff5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d2eb50b211620dbee09bc517dadffa1.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f5e3f03c2ff2b194b0aa216213c5bed.png)
更新时间:2016-12-04 03:29:31
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,
为空间四边形
的边
上的中点,
分别为
上的点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/4f153b30-759e-4d87-9d22-e4751de425fe.png?resizew=135)
(1)求证:
;
(2)求证:
必交于一点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1da2078b8e4cb44d7147917152d601e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7473497fee0257402b6318033c1ef7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cf33d73483c93f24cc6a1d76ef22ca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/481e426224c3a3ce9bb5a731eed81c40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e7bf7655d3cdd109aa5b46ea18946e7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/4/4f153b30-759e-4d87-9d22-e4751de425fe.png?resizew=135)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cb70c19693b6bde1f121cc3f9f0bf45.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ca5eb5bb50655067642e37f169e4fed.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.64)
【推荐2】如图,在四棱锥
中,
底面
,底面
是梯形,其中
,
,
与
交于点
,
是
边上的点,且
,已知
,
,
.
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/6dc4c0d1891a431b9e62126c5cd43400.png)
(1)求平面
与平面
所成锐二面角的正切;
(2)已知
是
上一点,且
平面
,求
的值.
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/49a6f09234564636b93240d487a7693c.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/0c243ca12f774235a5e54d84c0d4a081.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/7ae03d4e0c024545b4fdeb2f46174e7e.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/7ae03d4e0c024545b4fdeb2f46174e7e.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/fdc8bd39dddd41329a53e95021422eb4.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/4ba40b6b485045a99fc629217b7c0942.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/e28ddc1a12454662908d6d3ef66e62ea.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/0d7b9074a483495a8fb0253d80612dd0.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/b0a26727ba9244ada37cdfcc45d2726b.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/aed0ef1451cc4a9b955b00448c662144.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/3d006c911ac149f7807cc5eef7795e9d.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/b7e67d91fad04b04853b854d4ee833c2.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/1f7e351bbf584d3aa09744e3d4d0ee27.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/33c9102b5f9e4e0ca81f3178ed78ff5a.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/6f7a99c863f5487d9d6d6a8b0e5cc5ee.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/6dc4c0d1891a431b9e62126c5cd43400.png)
(1)求平面
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/4eae8ac521f3409ba34c46ed72a19f5e.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/7cccccb4aa7a42e5921755808efdf795.png)
(2)已知
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/064a1968570f4196848368cfbbe17756.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/ef3bd71924424ca9acd20f47b43d5a75.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/8132d8d0f4d14f2d8e280b0f8bc79fd3.png)
![](https://img.xkw.com/dksih/QBM/2015/6/19/1572132780638208/1572132786806784/STEM/880e70170f634d7a85235ba58882ea68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48458daf573dcfb15f1d78d39c243cf0.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,在四棱锥
中,
⊥底面
,底面
为正方形,
,
,
分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/2020/12/23/2620363624505344/2623028923441152/STEM/2bd2591b-6ba4-4b0d-941a-2d6c252e74ae.png?resizew=283)
(1)求证:
平面
;
(2)求证:
;
(3)设PD=AD=a, 求三棱锥B-EFC的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a4b8b69b419c557ba61a2bdfaf4066.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43d4c42112e0a22f240ce2ae432e5b4d.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://img.xkw.com/dksih/QBM/2020/12/23/2620363624505344/2623028923441152/STEM/2bd2591b-6ba4-4b0d-941a-2d6c252e74ae.png?resizew=283)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b6cc3789c0e9b7d1226aa0de3327599.png)
(3)设PD=AD=a, 求三棱锥B-EFC的体积.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】如图,在四面体
中,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/247782d8-abcb-4926-8487-2c774dad2c93.png?resizew=180)
(Ⅰ)证明:
;
(Ⅱ)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01cb45d783ceddadc9f3dbe3de572b2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b83cb6327dcbc8a998e6586bcfa7a3b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/15/247782d8-abcb-4926-8487-2c774dad2c93.png?resizew=180)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76d72a007e3c4a134956b0e3fbde5f46.png)
(Ⅱ)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ec2524be492bca0d1566bf848066f10.png)
您最近一年使用:0次