名校
1 . 如图,
为菱形,
,
,平面
平面
,点F在
上,且
,
分别在直线
上.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/16/d8462600-5618-438d-9e6c-c45c87bf0269.png?resizew=164)
(1)求证:
平面
;
(2)把与两条异面直线都垂直且相交的直线叫做这两条异面直线的公垂线,若
,MN为直线
的公垂线,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209acf15985d1ea1ad86fc4a37e38c0b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a1be17e0a3e51cde1f50f384198e71e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c99e6d75d606b5cae9392ecca969200.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/84f31a3724c639f88486f8356ca65397.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70daa268c7a0b17f39c1e6eba043a3b8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/16/d8462600-5618-438d-9e6c-c45c87bf0269.png?resizew=164)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac0b72906641ed13716cfbce50923282.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
(2)把与两条异面直线都垂直且相交的直线叫做这两条异面直线的公垂线,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3177a657a66974f53b49dc827b78c5c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70daa268c7a0b17f39c1e6eba043a3b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e66082fe6f392885b1e57db9ffb5602.png)
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2 . 设等差数列
的前
项和为
,公差为
,
,
,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/390636a89883bd64bf8da9bf8654aff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/948d42e08a69266bed4b18ef1af72427.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03a1e385bd995da60cad02a4236d9163.png)
A.![]() |
B.当![]() ![]() |
C.数列![]() ![]() |
D.记数列![]() ![]() ![]() ![]() |
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3 . 已知
与直线
交于
两点,且
被
截得两段圆弧的长度之比为
,若
为
上一点,则
的最大值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cec7942a5f1cfc08d239801e00f13d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/669e8dfb2b45e6f74d86408343a18fe2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5881f1ce9b4172ca346032d0fd1e3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/669e8dfb2b45e6f74d86408343a18fe2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f96e26a79d12063cdc069e72034df94.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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4 . 已知A、B、C、D、E、F六个人站成一排,要求A和B不相邻,C不站两端,则不同的排法共有( )种
A.186 | B.264 | C.284 | D.336 |
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5 . 如图,三棱锥
中,平面
平面
,平面
平面
,平面
平面
,
两两垂直;
(2)若
为
中点,
为
中点,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcf6dc837ae85207789b94d109c5c2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcf6dc837ae85207789b94d109c5c2eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0d3055b122bf4953a3d6cc92ab03d74.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de71ce866cd3325113f3324dc01b472a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6ede9761b5b90f8dc137708e1ee90f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
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名校
6 . 在学校食堂就餐成为了很多学生的就餐选择.现将一周内在食堂就餐超过3次的学生认定为“喜欢食堂就餐”,不超过3次的学生认定为“不喜欢食堂就餐”.学校为了解学生食堂就餐情况,在校内随机抽取了100名学生,统计数据如下:
(1)依据小概率值
的独立性检验,分析学生喜欢食堂就餐是否与性别有关:
(2)该校甲同学逢星期二和星期四都在学校食堂就餐,且星期二会从①号、②号两个套餐中随机选择一个套餐,若星期二选择了①号套餐,则星期四选择①号套餐的概率为
;若星期二选择了②号套餐,则星期四选择①号套餐的概率为
,求甲同学星期四选择②号套餐的概率.
(3)用频率估计概率,从该校学生中随机抽取10名,记其中“喜欢食堂就餐”的人数为
.事件“
”的概率为
,求使
取得最大值时
的值.
参考公式:
,其中
.
男生 | 女生 | 合计 | |
喜欢食堂就餐 | 40 | 20 | 60 |
不喜欢食堂就餐 | 10 | 30 | 40 |
合计 | 50 | 50 | 100 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f123c7e419fd409559c85afdb19ef067.png)
(2)该校甲同学逢星期二和星期四都在学校食堂就餐,且星期二会从①号、②号两个套餐中随机选择一个套餐,若星期二选择了①号套餐,则星期四选择①号套餐的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7294f5ae2a24ff42e84cd9773b2a7287.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
(3)用频率估计概率,从该校学生中随机抽取10名,记其中“喜欢食堂就餐”的人数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/875a413a7593078159ceda1319f965cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef133b0fd53a48310a82c18729575abd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef133b0fd53a48310a82c18729575abd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
参考公式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2187714e660234f0b72f2b47d3ea685a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/356b05e46b10ee51c3e43546d73ec96c.png)
0.1 | 0.05 | 0.01 | 0.005 | 0.001 | |
2.706 | 3.841 | 6.635 | 7.879 | 10.828 |
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7 . 已知
,下面结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75916b7ad4c895b7b8644d53f97ce673.png)
A.![]() ![]() ![]() |
B.若![]() ![]() ![]() ![]() |
C.若![]() ![]() ![]() ![]() |
D.存在![]() ![]() ![]() ![]() |
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8 . 在棱长为4的正方体
中,点
是棱
的中点,则四面体
的外接球的体积为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c27ae22ad74b412e6d71ec1245f802db.png)
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9 . 已知实数
,且满足
,当
取得最大值时,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5154ce098d83928b357e01070762413a.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360ff131c51a4ef6745538c18cec92c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dcf600445a2eeef7e18c8feb4b0e8bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f8d40e257f9c446b8e30fa841b74bbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5154ce098d83928b357e01070762413a.png)
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10 . 已知
分别为
三个内角
的对边,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3d2ad9a35995a5c3996eebc6b2eaaa8.png)
(1)求
;
(2)若
的面积为
,
为
边上一点,满足
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3d2ad9a35995a5c3996eebc6b2eaaa8.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a4baf1f5dcf7dccb47aad806845e134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f3ba8b214034c287276f4966069d95e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
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