在棱长为
的正方体
中,
、
分别是棱
、
上的点,且
.
(1)当
、
在何位置时,
?
(2)是否存在点
、
,使
平面
?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](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/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f805768a5ffaf8bdfa4bc3b680aafdc9.png)
(1)当
![](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/40e7c16fcd117047c6c81ab37118e4c5.png)
(2)是否存在点
![](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/d26d8a9d64ad3c8cba28840b41ed7837.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bff3ccea5989c60e51e321af3f53f54.png)
2019高二上·全国·专题练习 查看更多[1]
(已下线)2019年12月18日《每日一题》选修2-1理数-用向量法证明空间中的垂直关系
更新时间:2019-12-19 19:20:39
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】已知四棱锥
的底面
为菱形,且
,
,
,
与
相交于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/1180cd27-53de-4a5a-a91b-f512b407ca67.png?resizew=186)
(1)求证:
底面
;
(2)求直线
与平面
所成的角
的值;
(3)求平面
与平面
所成二面角
的值.(用反三角函数表示)
![](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/e075468e7fb0bf30229aec01a7205977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2551d93b674b9f8bcd0e88454c99eb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cb96e0331eebe80ed1ff610faf531fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/1180cd27-53de-4a5a-a91b-f512b407ca67.png?resizew=186)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6581916f5a65edfea257c804efee007e.png)
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【推荐2】如图,已知四面体ABCD的四个面均为锐角三角形,E、F、G、H分别为边AB、BC、CD、DA上的点,BD∥平面EFGH,且EH=FG.
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777367568384/1570777373065216/STEM/f22dd3b964d149cd8b4938a4bb7aabcd.png?resizew=133)
(1) 求证:HG∥平面ABC;
(2) 请在面ABD内过点E作一条线段垂直于AC,并给出证明.
![](https://img.xkw.com/dksih/QBM/2012/2/27/1570777367568384/1570777373065216/STEM/f22dd3b964d149cd8b4938a4bb7aabcd.png?resizew=133)
(1) 求证:HG∥平面ABC;
(2) 请在面ABD内过点E作一条线段垂直于AC,并给出证明.
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解答题-问答题
|
适中
(0.65)
【推荐3】已知三棱锥
中侧面
与底面
都是边长为2的等边三角形,且面
面
,
分别为线段
的中点.
为线段
上的点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/87fe5542-cf94-4982-95e5-a13a4a6c5f11.png?resizew=125)
(1)证明:
为线段
的中点;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcf6dc837ae85207789b94d109c5c2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6670479a0083dd2dfd5ad55b47b1ab6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdb2c8786b3375fa19b35cd9343a9b7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/070c1b240b1e5dab1e5242045c83c0ac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/23/87fe5542-cf94-4982-95e5-a13a4a6c5f11.png?resizew=125)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/337a7d93a297605aac575e7bbf693d28.png)
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【推荐1】在四棱锥
中,底面
是一直角梯形,
,
,
,
底面
,PD与底面成30°角.
(1)若
,E为垂足,求证:
;
(2)在(1)的条件下,求异面直线AE与CD所成角的余弦值;
(3)求平面
与平面
所成的锐二面角的正切值.
![](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/97e45b6f8cf0260912f587c04f9f2442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d04140df8b6986b5ec855a6059c4cb2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c40ad2d2c76f6db28c217624913f9371.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/304e9d63e7fdc531f4f7b805b765a1b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a03d3b1a7b201f380f960db4b6ff2943.png)
(2)在(1)的条件下,求异面直线AE与CD所成角的余弦值;
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://img.xkw.com/dksih/QBM/2012/1/6/1570679833305088/1570679838859264/STEM/ff473a18ab084531bd7669262ddc3b6b.png?resizew=171)
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名校
解题方法
【推荐2】如图,在平行六面体
中,设
,
,
,
分别是
,
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/5/4ab419a1-c111-4dca-951b-b019d6c020b7.png?resizew=169)
(1)试用
,
,
表示以下列向量:
.
(2)
,
,求证:
平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a08f3a88dffed011df93d1d606a08ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4f8173bb7787b6b107acfe767dd1d91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/232311b4261c36b659555a07bfa00f7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9369aed2d8309af46ac3eaffb9cce537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/5/4ab419a1-c111-4dca-951b-b019d6c020b7.png?resizew=169)
(1)试用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d366d8fbb7258ee051f49977441e14a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9048009c730b179d7cb1e7f2364c86be.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e95ebf110263f39285714fc68a6799d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13258ebc990cf559912cffc924dcac34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d1d2e0f281222a5f289ea4008370aed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】如图,
分别是四面体
的棱
的中点,
是
的三等分点(点
靠近点
),若
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/29/db3f5fea-2c8f-4f36-ba32-c648a8b64df6.png?resizew=176)
(1)以
为基底表示
;
(2)若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3241d7fedd89d85711acd7a2635298af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/881ec4ef24907683dd46062e5ff149c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2237240a3a5108783d1b90c0d7572806.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/29/db3f5fea-2c8f-4f36-ba32-c648a8b64df6.png?resizew=176)
(1)以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ed18a92338c7578c18a5ba3a2ae1ed4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4731335d26e45bf7041b36c5f0a1121d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0d27a9e2e35a727df29ff1d87d73dc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/694cdf60ef30ed1cede03a92e866d70c.png)
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解答题-问答题
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适中
(0.65)
【推荐2】如图,正方体
的棱长是
,
和
相交于点
.
![](https://img.xkw.com/dksih/QBM/2023/10/16/3347523684212736/3348238957027328/STEM/257ef09ebbc241c9b3cc78d9bfa8559e.png?resizew=146)
(1)求
;
(2)判断
与
是否垂直.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e539f26ed5e0b20ff7220559324869a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2eb89294b31ffdd2680b4361e8994d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/2023/10/16/3347523684212736/3348238957027328/STEM/257ef09ebbc241c9b3cc78d9bfa8559e.png?resizew=146)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1df1855bfa12d8aa6751780450be06dc.png)
(2)判断
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ef2723673c90347f6dd58346278c7fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d74ffe21e67d81dd25b6ab7b5cc30c08.png)
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