1 . 在三棱锥
中,
,
,
,
为
的中点,则异面直线
与
所成角的余弦值是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e240a6378adf6d23ebf9cc710c9bd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa7aeb2a8d1437eeb4482c3b6ad9f315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb322e81e7d2a672a901039600962316.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
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2024-06-12更新
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802次组卷
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3卷引用:辽宁省部分学校2024届高三抢分卷(三)数学试题
名校
解题方法
2 . 正三棱柱
中,所有棱长均为2,点E,F分别为棱
,
的中点,则直线EF与直线BC所成角的余弦值为_______ ;若过点A,E,F作一截面,则截面的周长为_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
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2023-07-13更新
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3卷引用:辽宁省锦州市2022-2023学年高一下学期期末数学试题
辽宁省锦州市2022-2023学年高一下学期期末数学试题(已下线)考点15 正弦定理、余弦定理的综合应用 --2024届高考数学考点总动员【讲】重庆市荣昌中学校2023-2024学年高一下学期4月期中考试数学试题
3 . 如图,在正方形ABCD中,点M,N分别是线段AD,BC上的动点,且
,MN从AB向CD滑动(与AB和CD均不重合),MN与AC交于E,在MN任一确定位置,将四边形MNCD沿直线MN折起,使平面
平面ABNM,则在滑动过程中,下列说法中正确的有____________ .(填序号)
的余弦值为
②AC与MN所成的角的余弦最小值为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174142f3bba761585b6bc2653009b36.png)
③AC与平面ABNM所成的角逐渐变小 ④二面角
的最小值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31307b00524e461b0ad8dfbcdf24bacf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6db4bd2cb84e75b6f8de1fa79e87ef01.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4598486f8c5ac28b1165b76e78105979.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1174142f3bba761585b6bc2653009b36.png)
③AC与平面ABNM所成的角逐渐变小 ④二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5617a404c5a3356753136e5a6b6d51e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
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名校
4 . 如图,棱长为1的正方体
,点
沿正方形
按
的方向做匀速运动,点
沿正方形
按
的方向以同样的速度做匀速运动,且点
分别从点A与点
同时出发,则
的中点的轨迹所围成图形的面积大小是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8776cb36494afe1f13cfc60099a973b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9961e091f180e964a962adf6916f33c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28af8d2c49057caaff1c1e2c4d5ef7c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
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2022-01-16更新
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7卷引用:辽宁省重点高中沈阳市市郊联体2023-2024学年高二上学期期末模拟数学试题
5 . 在棱长为
的正方体
中,
分别是棱
的中点,
为线段
的中点.若
分别为
的动点,则
最小时直线
与直线
所成的角的余弦值为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88eefaa74efafcea0c9f623190c3ddd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7f6f93171329d508d491143b9d71f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ffbc423070f5d7ce2c72229066ee1cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be87d6ce46a0b7ad88ce94758f866d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2bb1548ddc0e5536a35b1bd78c4e7cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/892909e49156f7dcc0650fcd65243877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c8ffe24cf9f327aeb241225ab15ab1a.png)
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名校
解题方法
6 . 在正方体
中,E,F分别为线段
,AB的中点,O为四棱锥
的外接球的球心,点M,N分别是直线
,EF上的动点,记直线OC与MN所成的角为
,则当
最小时,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85527d190d4e1d6bac4145d1c716e65e.png)
__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/405d0a18a50ffb68abef66ef058806d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22adbc0da438220f9cace11b629d799b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85527d190d4e1d6bac4145d1c716e65e.png)
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2020-08-13更新
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562次组卷
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6卷引用:辽宁省沈阳市郊联体2021-2022学年高二上学期10月月考数学试题