如图,在直三棱柱
中,
,
,点
是
的中点.
![](https://img.xkw.com/dksih/QBM/2017/11/3/1809205187305472/1809494277660672/STEM/522106bc97154329874a5cbb52e6690a.png?resizew=172)
①求证:
.
②求点
到平面
的距离.
③求二面角
的余弦值的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e96a6b20a35af7755e5d90789ea862da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.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/2017/11/3/1809205187305472/1809494277660672/STEM/522106bc97154329874a5cbb52e6690a.png?resizew=172)
①求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af42c7c4ceab6fef2931fc436218c2b3.png)
②求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc7e774e4ae40c23bf4ceed179230ca.png)
③求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55089af69fcfa82c2a34df1b4e1cabf0.png)
更新时间:2017-11-03 22:48:26
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在棱长为1的正方体
中,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2022/5/7/2974166728957952/2980029831782400/STEM/0dc6b421f1574a25bd038df160b183cd.png?resizew=203)
(1)求证:
平面
;
(2)求点
到平面
的距离;
(3)在对角线
上是否存在点
,使得
平面
?若存在,求出
的长;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/2022/5/7/2974166728957952/2980029831782400/STEM/0dc6b421f1574a25bd038df160b183cd.png?resizew=203)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/554923047631d16320c2ba39abeee99c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2331bccb6ebf5b9fd639df994f575a9.png)
(2)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2331bccb6ebf5b9fd639df994f575a9.png)
(3)在对角线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b301c74bfd4824215e12ce4504cfec1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2331bccb6ebf5b9fd639df994f575a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
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解答题-证明题
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名校
解题方法
【推荐2】如图,在四棱锥
中,
为平行四边形,
,
平面
,且
,点
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/7109b927-7381-424e-9d74-1f73e2d85d60.png?resizew=226)
(1)求证:
平面
;
(2)求
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bf01adbdbab49dc9915b957ddf85351.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.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/dc3d3b99bf26b53d61156fb9f1147123.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/editorImg/2022/11/29/7109b927-7381-424e-9d74-1f73e2d85d60.png?resizew=226)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30067b7b236d17af8a462f96a58d11bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
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【推荐1】如图,在四棱锥
中,底面
为菱形,顶点
在底面
的射影恰好是菱形
对角线的交点
,且
,
,
,
,其中
.
![](https://img.xkw.com/dksih/QBM/2019/4/22/2188035238281216/2188784744718336/STEM/30a8f3b3-0516-4c17-810a-b2787f958bb9.png)
(1)当
时,求证:
;
(2)当
与平面
所成角的正弦值为
时,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/dad2a36927223bd70f426ba06aea4b45.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/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e918b70b02a73685e3c536c7f380e2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85aeab3aeaf4367b711da8cde2e8bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e18614ed6ad3b4727d3920d8e2fb4454.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/540ccd15435aa2d59e809d6a28fb2467.png)
![](https://img.xkw.com/dksih/QBM/2019/4/22/2188035238281216/2188784744718336/STEM/30a8f3b3-0516-4c17-810a-b2787f958bb9.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f83464bf17f9d4d9ee6a7f299539871.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b53261da24d5257c7ecb6183f061752.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83303d3784492506fc44f2b4d6b07bc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32df383b8e2e1f012a116d16a91e1c44.png)
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解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图在四棱锥
中,底面
为菱形,
,点
为线段
的中点且
,设平面
与平面
的交线为直线
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/83cba47b-be84-415a-a0b3-e1d3dce6a74e.png?resizew=167)
(1)证明:直线
平面
;
(2)若
,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/3c7e3b6c68c625d489c3977a4fac335d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9829fc6685b59fdc609f32f30ebd9e6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/28/83cba47b-be84-415a-a0b3-e1d3dce6a74e.png?resizew=167)
(1)证明:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4d5240f8aed282883ca120c6e80d200.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c77e96fa5a272f0f0bd8ad4207cbd9a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e867e5c7ef4da37d8985ce82022060e.png)
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解答题-证明题
|
适中
(0.65)
【推荐3】已知
是正方体,点E为
的中点,点F为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/13/3d1ea19d-e2df-4bb3-97b7-c5bfc250d1cd.png?resizew=170)
(1)求证:
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/13/3d1ea19d-e2df-4bb3-97b7-c5bfc250d1cd.png?resizew=170)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddc8d7854010461e187f817b81e3f351.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a26da65c1bccce34970ea92815c31e8.png)
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