在四棱锥
中,
平面
,
,
,
,
,
分别是
的中点.
![](https://img.xkw.com/dksih/QBM/2022/1/13/2893833168044032/2895196300410880/STEM/5c86629b5da840feae5ba5ca075efbda.png?resizew=174)
(1)求证:
平面
;
(2)求证:
平面
;
(3)求直线
与平面
所成角的正弦值.
![](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/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf2e356de1dec9ce998366a1a35c0a9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037b342a682cbd4241855a243da3c016.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/227c1d105f7abf228e7a4f3097ae93f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea73441d3e6e07362ad5b35d122c0a3e.png)
![](https://img.xkw.com/dksih/QBM/2022/1/13/2893833168044032/2895196300410880/STEM/5c86629b5da840feae5ba5ca075efbda.png?resizew=174)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662698361c6b3ddaf0c28a3c87be53e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
更新时间:2022-01-15 21:14:51
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,
平面
,
,
,
,
为
中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/18b9bac0-d4de-4d6c-9b69-747b73fead9c.png?resizew=233)
(1)求证:BC//平面
;
(2)求直线
与平面
所成角的正弦值.
![](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/52a923784f083b7f4777891afe06b44e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f8eeeea1c9652cacce976f8129cf520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c14a66ed4bd66df65bc42c4ac1ed15c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7aa1162d5481e2441fe5bc0d49a576b0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/18b9bac0-d4de-4d6c-9b69-747b73fead9c.png?resizew=233)
(1)求证:BC//平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
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解答题-问答题
|
适中
(0.65)
【推荐2】如图,四棱锥
的底面为矩形,
底面ABCD.过AD的平面
分别与线段
相交于点E,F.
![](https://img.xkw.com/dksih/QBM/2022/7/7/3017413551013888/3017438036566016/STEM/f0381e4688b94813a9c95315990e244b.png?resizew=241)
(1)证明:
;
(2)若
,试问是否存在平面
,使得直线PB与平面
所成角的正弦值为
?若存在,求出此时BE的长;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589c3cc1f331dbb2248b0829039df7f3.png)
![](https://img.xkw.com/dksih/QBM/2022/7/7/3017413551013888/3017438036566016/STEM/f0381e4688b94813a9c95315990e244b.png?resizew=241)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4ffb68a9ca3bf66788363bc89dab45.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8fcb69d764f90b5d6146e27cb8f5841.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24c14ff9b66f21c05e52dc3c8908c2df.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】在直三棱柱
中,
,
,
分别为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/b856458c-3f10-40d7-ae75-68245f60e3de.png?resizew=152)
(1)求证:
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b9223c911c1c0ce39bc39cde160cb98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbfb9c088a7422e95f747701a626513d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/b856458c-3f10-40d7-ae75-68245f60e3de.png?resizew=152)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c7f786fc33d0506d64047034e12fd7a.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38a0d7b8e606b160f5751a1ec5d3a92a.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】如图,已知矩形ABCD中,AB=1,BC=![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
,PA
平面ABCD,且PA=1.
(1)问BC边上是否存在点Q,使得PQ
QD?并说明理由;
(2)若边上有且只有一个点Q,使得PQ
QD,求这时二面角Q
的正切.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6369ea989d998028ed1474f6645ec9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4237f6a1fc115bb790aa10704b7908c3.png)
(1)问BC边上是否存在点Q,使得PQ
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4237f6a1fc115bb790aa10704b7908c3.png)
(2)若边上有且只有一个点Q,使得PQ
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4237f6a1fc115bb790aa10704b7908c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f7c0df91cab39eb600a0785caf5f0.png)
![](https://img.xkw.com/dksih/QBM/2012/5/14/1570854070558720/1570854075760640/STEM/dfbc05264cc54941827a48e78a8e5810.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】在四棱柱
中,
底面
,底面
为平行四边形,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/31/57476b51-ace1-4975-953c-3d2a6f68bcd0.png?resizew=162)
(1)证明:
平面
;
(2)求
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/9ddbb0422a136f45653c8c369f2d75fc.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/7c9cce9e947a01fd80c2e806e2b33a20.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/31/57476b51-ace1-4975-953c-3d2a6f68bcd0.png?resizew=162)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4da530384dd04ac90a025385e8b3c2f.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/679748eab882a6be0fefd2cc300349a4.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,已知三棱柱
的所有棱长均为2,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/458a3ae7-a63f-4b71-a589-3b013f113612.png?resizew=229)
(Ⅰ)证明:
;
(Ⅱ)若平面
平面
,
为
的中点,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abbb4afeaca62289bbd780e672d29868.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/20/458a3ae7-a63f-4b71-a589-3b013f113612.png?resizew=229)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb81a917e1183890a82885b350b63f14.png)
(Ⅱ)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85a2e10a5aebe40a9018d5ee3ade7af8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/770b4f16694b2bd79a1a93d776a82680.png)
您最近一年使用:0次