1 . 2022年8月某市组织应急处置山火救援行动,现从组织好的5支志愿团队中任选1支救援物资接收点服务,另外4支志愿团队分配给“传送物资、砍隔离带、收捡垃圾”三个不同项目,每支志愿团队只能分配到1个项目,且每个项目至少分配1个志愿团队,则不同的分配方案种数为( )
A.36 | B.81 | C.120 | D.180 |
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2023-01-13更新
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6卷引用:黑龙江省鹤岗市第一中学2022-2023学年高二上学期期末数学试题
黑龙江省鹤岗市第一中学2022-2023学年高二上学期期末数学试题重庆主城区2023届高三一诊数学试题(已下线)专题3 排列组合、二项式定理、古典概率(已下线)专题十 计数原理与概率统计-1(已下线)模块一 专题5 排列与组合(讲)(已下线)模块一 专题7 排列与组合(苏教版)
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2 . 等腰梯形
中,
,
,
.若点
、
均在
上,且
.如图(一)所示,沿
将
折起,沿
将
折起,使
、
两点重合为
.
(1)若
,如图(二)所示,求证:平面
平面
;
(2)若
,
为
中点,当
与
重合于
时,如图(三)所示,求
与平面
所成角的余弦值;
(3)请设计一个翻折方案使四棱锥
的外接球半径为
,证明你的结论,并求此方案下的
的长度及
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b040eb31b0b7073ad3ffa8bd7968d187.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037b342a682cbd4241855a243da3c016.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04f8eebda19eded2b059774a8c2666c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6830ebecddbd9759be626289c408e4f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/27/ba897f14-f9d7-44dc-b819-8c1cfd0adc02.png?resizew=459)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27aa17bad024a9361bd0a679e10f70ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6bec37dca00db5f4512ce70f16ceb20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3747e528a1e8d45668ccf835c0175a73.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f4aca5534bce25acaeb7379deed8f8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.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/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18e5ef91fb27dd684a27ae7f1993cfba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ef796b46e68fe77b117ff0483d2370c.png)
(3)请设计一个翻折方案使四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff027309f3108559e6b3915158a3867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b3b0b11a80e8b107e55534d7fda9f2b.png)
您最近一年使用:0次
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解题方法
3 . 哈六中戏剧节比赛,11——15班这5个班级安排在周一至周五的中午进行表演,每天中午安排一个班级,且14班要安排在周一中午或周二中午,则不同的安排方案有( )
A.24种 | B.48种 | C.96种 | D.120种 |
您最近一年使用:0次