在如图所示的多面体中,
平面
平面
,且
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/9/0f395a70-88e4-42d9-a4d6-2fdaa44c2ab6.png?resizew=219)
(1)求平面
与平面
所成的锐二面角的余弦值;
(2)在棱
上是否存在一点
,使得直线
与平面
所成的角为
.若存在,指出点
的位置;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed04b01505bbd8a4ac0bc12e46f23bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49ce9b8e1b049cebd811b399c018b919.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92dbb4a08b5906ee4b6d74fcd9287974.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1df05856faae8670e41719807334d488.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/9/0f395a70-88e4-42d9-a4d6-2fdaa44c2ab6.png?resizew=219)
(1)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/558ce69401f3c97930f00ba0e2aa6647.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/558ce69401f3c97930f00ba0e2aa6647.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
更新时间:2021-12-08 11:29:54
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,
平面
,
,点
分别为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/a30c0447-f790-4a76-837e-5958360079b1.png?resizew=185)
(Ⅰ)求证:
平面
;
(Ⅱ)求二面角
的正弦值;
(Ⅲ)若
为线段
上的点,且直线
与平面
所成的角为
,求线段
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d7910956bbba8ef006f21919ba381f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdf7ab831f4d2053cbd4a6d63ad7ac5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd432f644b073d03f1d756df3c3987c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dd47a5f168dbbe5c0bfec5e7dfb5687.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/17/a30c0447-f790-4a76-837e-5958360079b1.png?resizew=185)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f16835e3f230ba3f543b6804e445e283.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fcce61c3d158b5331d6de10db3fb55d.png)
(Ⅱ)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24aca9af25c07f031e00ad681d3d9978.png)
(Ⅲ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f53330c107f8245290a5a42c3d356acd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3533837e3d08c461dea031a44e5424d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/358cdecf669033e648c21dcf675df9b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce2790947716b1cfa9c5e7a65db4093.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,在四棱锥
中,侧面
为等边三角形且垂直于底面
,
,
.
,
是棱
上的动点(除端点外),
分别为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/12/390765f6-696e-4ff0-b65d-4a5a4edff687.png?resizew=189)
(1)求证:
平面
;
(2)若直线
与平面
所成的最大角为30°,求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0041488020a3e19377b18a70fbf82e7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a56afb8c84a2105d525b84b6862a5426.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f3a221f7ecf69a6bb147c2e6a0626d6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/12/390765f6-696e-4ff0-b65d-4a5a4edff687.png?resizew=189)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39284c1ef4a749b8683a7c79c4246672.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
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解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,已知直三棱柱
中,
且
分别为
的中点,
为线段
上一动点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/6/93577e24-2083-4d3e-9590-6c34f2c17a7c.png?resizew=138)
(1)求
与平面
所成角的正切值;
(2)求点
到平面
的距离;
(3)求锐二面角
的余弦值的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a9ad711b25c36dae0c2a2cedff9954.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35e53bde928275ba6269c58754870b66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b578b4454bdaca362252d9283fcca2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/6/93577e24-2083-4d3e-9590-6c34f2c17a7c.png?resizew=138)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/456175ea34492f0bc025aaab668fa659.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
(2)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/481a69ce98c49013db26c6c7da7a0562.png)
(3)求锐二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34d9892555bfe67259e3e5a1fff78976.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,四棱锥
中,底面
为菱形,
平面
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2017/9/14/1773800893161472/1775384856289280/STEM/785acae912ba403c8a8c17b23c15f6cc.png?resizew=143)
(Ⅰ)证明:
平面
;
(Ⅱ)设
,三棱锥
的体积为
,求二面角
的余弦值.
![](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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2017/9/14/1773800893161472/1775384856289280/STEM/785acae912ba403c8a8c17b23c15f6cc.png?resizew=143)
(Ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa69a2247ad4d5231aa361349b12f97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
(Ⅱ)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd36be16e31d1bf8eadc0e31583a539.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b565e518d475a50358fedff2f0bb8dec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42ec13ca7115ccd73a9d793758f1c170.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03a08e6ea74ee085ed9dd4a05af94c2.png)
您最近一年使用:0次