如图,在四棱锥
中,
底面
,
,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2021/5/13/2720233920348160/2805898438156288/STEM/3b97454daa77496dbea9929de86b55e2.png?resizew=183)
(1)证明
平面
;
(2)求二面角
的正切值.
![](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/35cef70b864b5e128a0828e304e3a4b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ace900749d0861aa51fcc6d72c51f82c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/2021/5/13/2720233920348160/2805898438156288/STEM/3b97454daa77496dbea9929de86b55e2.png?resizew=183)
(1)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e867e5c7ef4da37d8985ce82022060e.png)
更新时间:2021-09-11 17:17:53
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,在四棱柱
中,
底面
,
,
,且
,
.点
在棱
上,平面
与棱
相交于点
.
(1)求证:
平面
.
(2)求证:
平面
.
(3)求三棱锥
的体积的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1ecf072589c0f901d92f6bda111d841.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce0d7095ddd69d6ceaf1065b1bc2c79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bdc0b1d129b086faf83d192decd9f48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f233b375753611ffa7a93c2c12ef5e28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5d45c10c00742e89d4123977720c0e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b886daa3c9bb7153acd9f651f99eb2c1.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56fdf217165748fafe938b64fa08179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82b724168afaee2ecddf97257180be18.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/984a09f427670c29013a0b3e89a5ea94.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/4/657a6f82-4e89-4a87-99a9-8a6e6ecd9986.png?resizew=191)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】在正方体
中,
,
分别为
,
的中点
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/ae05b690-f6f9-40c3-a3e4-8132e216bc7e.png?resizew=172)
(1)求证:
面
;
(2)在棱
上是否存在一点
,使得
面
,若存在,试确定
的值,若不存在说明理由;
(3)在(2)的条件下,求面
与面
所成二面角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/8/ae05b690-f6f9-40c3-a3e4-8132e216bc7e.png?resizew=172)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd0cb774b7e17aaf31faa00741db2330.png)
(2)在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf2ffe6d4f6b90b39733328d39a1d494.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f73add9a225f7b7fd1ca717cc49f766.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab0eeb332741f0ef7c6c863406ff22f0.png)
(3)在(2)的条件下,求面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd0cb774b7e17aaf31faa00741db2330.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f73add9a225f7b7fd1ca717cc49f766.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】已知平行四边形ABCD中,AB=6,AD=10,BD=8,E是线段AD的中点.沿BD将△BCD翻折到
,使得平面
平面
.
![](https://img.xkw.com/dksih/QBM/2013/5/20/1571221982478336/1571221988098048/STEM/130646ff3e204212b4c2f0f3cb17b2bd.png?resizew=208)
(Ⅰ)求证:
平面ABD;
(Ⅱ)求直线
与平面
所成角的正弦值;
(Ⅲ)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e2d3dc7c3b68e9acf4ab4f8bd5b545.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/583dc7946f12e23433a9d9217a861adc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://img.xkw.com/dksih/QBM/2013/5/20/1571221982478336/1571221988098048/STEM/130646ff3e204212b4c2f0f3cb17b2bd.png?resizew=208)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/193fec6e443715a66e5fc77a4a7ae0d2.png)
(Ⅱ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/330808dc42f8e244c35791d572d83a57.png)
(Ⅲ)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe2bfe6bca093daec833b0dcada3690b.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2】(1)在如图所示的正方体中,M,N分别为棱
和
的中点,求异面直线
和
所成的角的大小.
![](https://img.xkw.com/dksih/QBM/2021/12/15/2873154521276416/2873301331566592/STEM/95a89e6a98514a07be1371bb2357e73a.png?resizew=228)
(2)如图,在四棱锥
中,底面是边长为a的正方形,侧棱
,求二面角
的平面角的大小.
![](https://img.xkw.com/dksih/QBM/2021/12/15/2873154521276416/2873301331566592/STEM/c2bcbee9014845fd8cd6785d192af202.png?resizew=211)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://img.xkw.com/dksih/QBM/2021/12/15/2873154521276416/2873301331566592/STEM/95a89e6a98514a07be1371bb2357e73a.png?resizew=228)
(2)如图,在四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd9387a4138ea2a094e37f86cc889a12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/715cc9ea5e7d80930284ffb117142770.png)
![](https://img.xkw.com/dksih/QBM/2021/12/15/2873154521276416/2873301331566592/STEM/c2bcbee9014845fd8cd6785d192af202.png?resizew=211)
您最近一年使用:0次