如图,在正方体
中,点E,F分别在棱
,
上,且
,
,尝试用不同的方法求BE与DF所成角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e26d9636ad77369535852c6e4493446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88691e03c85ee6aa5fbfcffa154eb8f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b232d4f29018b8fba30ff5958ab360b6.png)
21-22高二·湖南·课后作业 查看更多[2]
更新时间:2022-03-05 21:40:14
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相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】如图所示,在四棱锥
中,
平面
,
,
,
是线段
的中垂线,
,
为线段
上的点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/9d023804-8a5d-4f99-ad07-135ddb7c358c.png?resizew=169)
(1)证明:平面
平面
;
(2)若
为线段
上的中点.,求异面直线
与
所成角的正切值;
(3)求直线
与平面
所成角的大小.
![](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/204fb7cfd350a616164c68ec109880ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2c4451756598365df5929f91cffaf9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5aa1a7d0640af8f8b225044a4b566b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/28/9d023804-8a5d-4f99-ad07-135ddb7c358c.png?resizew=169)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6d0567ee284567a5d42b3c0b95083ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce8f887360a533f0a25b0b34fb11f0a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4d775e9fb8bca58a25e75d5b21b05f.png)
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解答题-证明题
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适中
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真题
【推荐2】如图,在四棱锥
中,底面
是矩形.已知
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/ca4e64ae-d14a-4684-b7a6-b43e69b92361.png?resizew=146)
(Ⅰ)证明
平面
;
(Ⅱ)求异面直线
与
所成的角的大小;
(Ⅲ)求二面角
的大小.
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/7e1b5ac446dd4ad79b80f336aed4c3de.png)
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/ccd3c2c2b43644f6a32e7a078815efa3.png)
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/288b0bea33cf4320af068342be222a6e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/ca4e64ae-d14a-4684-b7a6-b43e69b92361.png?resizew=146)
(Ⅰ)证明
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/099204761f1e48659276013e698d6eec.png)
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/1cdd7004ad79445cb432e2d4aa914500.png)
(Ⅱ)求异面直线
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/25d0d54224c24588b123e89bf4d092ff.png)
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/8c022303c8134ef4857c79cdaa8cc7bd.png)
(Ⅲ)求二面角
![](https://img.xkw.com/dksih/QBM/2010/4/1/1569688487706624/1569688630018048/STEM/5de2e71fb363459db4db522a7bb8a9ca.png)
您最近一年使用:0次
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适中
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解题方法
【推荐1】如图
,
是正三角形
的边
上的高,
是
的中点,现将三角形
沿
折起,使得平面
平面
,如图
.
(1)求异面直线
与
所成角的余弦值;
(2)在线段
上是否存在一点
,使
?若存在,求出
点的位置;若不存在说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06123e81c41198c76a3335757fac2c93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4739afd7311501e948aa4e1e5c1cb17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/22fb92c1-ee58-4644-aac8-b996fad0ac1d.png?resizew=349)
(1)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e32cf73c01995c91c3523fa11b3bd7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.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】如图所示的正四棱柱中,
,
,M是棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/14/932dc407-965b-4338-9501-eb041e95046c.png?resizew=119)
(1)求异面直线
和
所成的角的余弦值;
(2)证明:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc416a5b8dc234628e7475387888d82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/14/932dc407-965b-4338-9501-eb041e95046c.png?resizew=119)
(1)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91a2712f9cc643d4983d37c9dfe880ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adfc67f86e81cdd466230531ac658016.png)
您最近一年使用:0次