在棱长为2的正方体
中,
分别为棱
和
的中点.
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
平面
;
(2)求异面直线
与
所成的余弦值;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52041559f8fee18bfa3e2e2ac07c3bfa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bb10d645970e5860afd3430957fab6c.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e72b2e1ff83e95df048745322982451.png)
更新时间:2023-05-05 12:26:20
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】
的内角
的对边分别为
.已知
.
(1)求
;
(2)若
,
,求
的周长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6402f1010e94be78552ed4c45548b1b8.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e57152f1bd6a622070a8878b7f811731.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解答题-问答题
|
适中
(0.65)
【推荐2】在
中,三边a,b,c满足:
.
⑴探求
的最长边;
⑵求
的最大角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9178fc8b5d65aa75fa9196294a0db7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ada0dda08ca76bd142cf05c3391ca51a.png)
⑴探求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9178fc8b5d65aa75fa9196294a0db7e.png)
⑵求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9178fc8b5d65aa75fa9196294a0db7e.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,已知矩形ABCD所在平面外一点P,
平面ABCD,E,F分别是AB,PC的中点.且
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/29/de010fc4-6b31-4d4c-904a-d818642a0ba7.png?resizew=182)
(1)求EF与AD所成的角;
(2)求平面EFB与平面ABCD所成锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c2753753faf2cb9a0003aa8e3945159.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/29/de010fc4-6b31-4d4c-904a-d818642a0ba7.png?resizew=182)
(1)求EF与AD所成的角;
(2)求平面EFB与平面ABCD所成锐二面角的大小.
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解答题-问答题
|
适中
(0.65)
解题方法
【推荐2】在四棱锥
中,底面
是矩形.已知
,
,
,
,
.
(1)证明:
平面
;
(2)求异面直线
与
所成的角的正切值的大小;
(3)求二面角
的正切值的大小.
![](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/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed6281306726065e7075c579b9b66537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42e12bfde565540f059dd27ea47dfaa7.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/053af8641980763a7f0e77beefe0712d.png)
您最近一年使用:0次
【推荐1】如图,在直三棱柱
中,
,
,点
为
中点,连接
、
交于点
,点
为
中点.
(1)求证:
//平面
;
(2)求证:平面
平面
;
(3)求点
到面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78f7050f3151f3107611ddfef1709eef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/269c684310d0f7b5b9bf0a291e7ee748.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.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/f2eb89294b31ffdd2680b4361e8994d7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/16/a478ba64-960a-42fc-a082-54cff1071d7b.png?resizew=141)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54415b35519030aaa5f7edf879f1160c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.png)
(3)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.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,在直三棱柱
中,
,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/30/ba805054-e976-41b7-9a11-9de44ec6edaf.png?resizew=194)
(1)求证:
平面
;
(2)求二面角
的余弦值;
(3)试问线段
上是否存在点
,使
与面
所成角的正弦值为
?若存在,求出此时
的长,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3054bfbd706c492cba96b09d5780e2aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/30/ba805054-e976-41b7-9a11-9de44ec6edaf.png?resizew=194)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ebe6a446b91e73b181f9f4d56264dd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ba9e20d667d04bf3ee7f55cc795ce01.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f25c5543b39190dc2499aa66f939659.png)
(3)试问线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ba9e20d667d04bf3ee7f55cc795ce01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
您最近一年使用:0次