如图所示的多面体,其正视图为直角三角形,侧视图为等边三角形,俯视图为正方形(尺寸如图所示),E为PA的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/9a3621b5-7c5d-4944-a868-b8d6147d7e18.png?resizew=274)
(1)求证:
平面EBD;
(2)求二面角
的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/24/9a3621b5-7c5d-4944-a868-b8d6147d7e18.png?resizew=274)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b70cef0b79ca64acbb67dc667fc53b3.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02535e1a690ca111ca7a395a1bf48080.png)
更新时间:2022-11-21 22:28:56
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】如图,多面体ABCD﹣EFG中,底面ABCD为正方形,GD∥FC∥AE,AE⊥平面ABCD,其正视图、俯视图如下:
(I)求证:平面AEF⊥平面BDG;
(II)若存在λ>0使得
,二面角A﹣BG﹣K的大小为60°,求λ的值.
(I)求证:平面AEF⊥平面BDG;
(II)若存在λ>0使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6987bfcb8ad393226a90892ea3261e0a.png)
![](https://img.xkw.com/dksih/QBM/2011/4/11/1570115433324544/1570115438198784/STEM/cac5e02b9130464ea7ac56f57361002f.png?resizew=227)
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2】如图所示的多面体,其正视图为直角三角形,侧视图为等边三角形,俯视图为正方形(尺寸如图所示),E为PA的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/23/82f70672-7d2e-42d0-b025-b083a7073708.png?resizew=364)
(1)求证:
平面EBD;
(2)求三棱锥
的体积.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/23/82f70672-7d2e-42d0-b025-b083a7073708.png?resizew=364)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bb178784aa857d4d4683e650273f054.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42020cfacd62b300cad053981bab9e0b.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】在四棱锥
中,底面
为正方形,
平面
,E为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/13/f6846e99-116f-4035-8055-23223c11febb.png?resizew=200)
(1)证明:
平面
;
(2)若
,
,求直线
与平面
所成的角正切值.
![](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/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/13/f6846e99-116f-4035-8055-23223c11febb.png?resizew=200)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa69a2247ad4d5231aa361349b12f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc11331a7b2d2619b40ee6d34c3bd620.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.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2】如图,边长为
的正方形
所在平面与正三角形
所在平面互相垂直,
分别为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/4adaf677-1ff6-43c3-bbd1-2e837a10cebf.png?resizew=199)
(1)求四棱锥
的体积;
(2)求证:
平面
;
(3)试问:在线段
上是否存在一点
,使得平面
平面
?若存在,试指出点
的位置,并证明你的结论;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbab055d241f3c9d8bdec0c06d32bda3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62794ea73abc2a84aa0512c5b205eb12.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/12/4adaf677-1ff6-43c3-bbd1-2e837a10cebf.png?resizew=199)
(1)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8c2b786c64e6a9ed2ec5670cde74f86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9af29254fe60a392c249c5791279e9c8.png)
(3)试问:在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a74d65b2c8e7c219c25d2d7cd549c30b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c51c4a1148587943fe9ba210f6141ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图, 在直三棱柱
中,
,点
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/14/b1d3e46c-2e0c-4460-98e2-cb8e0a00d963.png?resizew=153)
(1)求证:
;
(2)求证:
平面
;
(3)求直线
与平面
所成角的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62508363b7b1497710de170e91c2a76e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/14/b1d3e46c-2e0c-4460-98e2-cb8e0a00d963.png?resizew=153)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/429228f882da65a8e0064c88d02b8e40.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4557a368725226f2c8ea2efb7d30e478.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc7e774e4ae40c23bf4ceed179230ca.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在六棱锥
中,底面
是边长为
的正六边形,
.
![](https://img.xkw.com/dksih/QBM/2020/6/25/2492107980488704/2493701708906496/STEM/c86620b9802540998ff1d01f656148a7.png?resizew=250)
(1)证明:平面
平面
;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3b7838a53d0b3ed4565fb6a890f365d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/458b6c1f8e142098dacb00c24c76aeb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dedc77cf35f230fa61c3dd7fc3124750.png)
![](https://img.xkw.com/dksih/QBM/2020/6/25/2492107980488704/2493701708906496/STEM/c86620b9802540998ff1d01f656148a7.png?resizew=250)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64eb31601464364be2baf4aa87404bcd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0df49b91d399a0b28d5ad86b84b1f42d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77355acc2b446cb1466cbd0462d26756.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图①所示,四边形
为等腰梯形,
,且
于点
为
的中点.将
沿着
折起至
的位置,使得平面
平面
,得到如图②所示的四棱锥
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/af2fd598-ef45-4147-b869-0285bfcbd60f.png?resizew=437)
(1)求证:
;
(2)求平面
与平面
所成的锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/247e96a3a378741eb42dda3837ea5c7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc3814287dbb60d478bffc5366f9928b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/353732838789714499619085201305c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33719580ce50fafc3a27eb7039be8a97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6bfad3f7e65188bcf7f62ea5acdbf4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/decee6072217173778edc84db382f97b.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/22/af2fd598-ef45-4147-b869-0285bfcbd60f.png?resizew=437)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c723ad583a4009b7a5dd515e7e02b8a.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a7f857869bc6084d128e8c13f5c115c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6bfad3f7e65188bcf7f62ea5acdbf4a.png)
您最近一年使用:0次