如图,在四棱锥
中,
底面
,
,
,
,
为
的中点.
![](https://img.xkw.com/dksih/QBM/2019/1/29/2129125985869824/2129740024487936/STEM/74990b8ce7374eca90781db39c3d4781.png?resizew=330)
(1)求证:
平面
;
(2)若
为
的中点,求点
到平面
的距离.
![](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/a1cb23cb7d9f22cfc31a6cd6fcb12e13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc532cfe64300cb3da9e04a307c957a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26eba7e649fade39fd2d0b6ef4ac5ffd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2019/1/29/2129125985869824/2129740024487936/STEM/74990b8ce7374eca90781db39c3d4781.png?resizew=330)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d246f9eceab371ebf47a47c2f11a4ad.png)
更新时间:2019-01-30 09:50:04
|
相似题推荐
解答题-证明题
|
适中
(0.65)
【推荐1】长方形
中,
,
是
中点(图1).将△
沿
折起,使得
(图2).在图2中:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c4e4a162f12d12a082b8d8fdd1aeab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ddb7c2ca1b6bee86cb24fed02e40da2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/804c0e2a375b5f4ff1c420532968efc3.png)
(1)求证:平面平面
;
(2)若,
,求三棱锥
的体积.
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解答题-问答题
|
适中
(0.65)
【推荐2】如图,在正方体
中,
是
的中点,
是
内部或边界上的点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/10/c7067edd-53c7-4610-aa6e-4a4f62c3471f.png?resizew=162)
(1)证明:
平面
;
(2)求直线
与平面
所成角的正弦值的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9a0c3a4e61b97fa9bc58f3179fc2958.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abf80148409afb32ced0b4f59f1ba709.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8385e82b5db466dbec438443a39934cf.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/5/10/c7067edd-53c7-4610-aa6e-4a4f62c3471f.png?resizew=162)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/932a04304f2d4975955d4baabb2deeea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29953579af8f8458bd3be0d75491da4f.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29953579af8f8458bd3be0d75491da4f.png)
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解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】已知直三棱柱
中,侧面
为正方形,
分别为
和
的中点,
为棱
上的动点(包括端点).
,若平面
与棱
交于点
.
与棱柱的截面,并指出点
的位置;
(2)求证:
平面
;
(3)当点
运动时,试判断三棱锥
的体积是否为定值?若是,求出该定值及点
到平面
的距离;若不是,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9edc50f7febbc2d5d8dcdc23a3630a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f223fc5e06e361260e74c9683677b18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e0af8c959d6c754ca6f3a074557da0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/914d46f7e72b55d2ff3d9bc38e02b31d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/914d46f7e72b55d2ff3d9bc38e02b31d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fa3c61d6c19e187b4b824b6f5610cdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/914d46f7e72b55d2ff3d9bc38e02b31d.png)
(3)当点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db26bad88328665735fadf82f44d6730.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe8a84ca3a13f82aff1a022edc66065.png)
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解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐2】如图,
是边长为3的正方形,
平面
,
,
,
与平面
所成角为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/7/aaca97ca-f4ea-4e69-9ca1-76f1447614a9.png?resizew=180)
(1)求A到平面
的距离;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8d2d217e9bcd059908f117dfc4d4259.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8139d9fd5c670c91aa7dc485366dd1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c5624c7941eb3cca11d8efbe76d9af5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/7/aaca97ca-f4ea-4e69-9ca1-76f1447614a9.png?resizew=180)
(1)求A到平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f717b7d4d0978eec7330afec554c078.png)
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解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐3】我国古代数学名著《九章算术》中,将底面为直角三角形且侧棱垂直于底面的三棱柱称之为堑堵;将底面为矩形且一侧棱垂直于底面的四棱锥称之为阳马;将四个面均为直角三角形的四面体称之为鳖臑[biē nào].某学校科学小组为了节约材料,拟依托校园内垂直的两面墙和地面搭建一个堑堵形的封闭的实验室
,
是边长为2的正方形.
![](https://img.xkw.com/dksih/QBM/2020/4/30/2452895398494208/2453578971889664/STEM/e0962971ca954fad8c6f2d3f105a1477.png?resizew=158)
(1)若
,
在
上,四面体
是否为鳖臑,若是,写出其每个面的直角:若不是,请说明理由;
(2)当阳马
的体积最大时,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9b7b7793d29d66dfdd89e7a6564a35c.png)
![](https://img.xkw.com/dksih/QBM/2020/4/30/2452895398494208/2453578971889664/STEM/e0962971ca954fad8c6f2d3f105a1477.png?resizew=158)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a543df08305d4a848a980969bb002a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f22725912baecf50924d950b915d0156.png)
(2)当阳马
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb1b9bf22bd3ca350a2651a7550e8ba1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
您最近一年使用:0次