1 . 考虑
的非空子集
,满足
中的元素个数等于
中的最小元素,例如,
就满足此条件. 则这样的子集
共有______ 个.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/477aaa8eb4961a77a717ee664fd021ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/765272efc14488ec658fc3302c5e6cc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
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解题方法
2 . 为参加一年一度的省高中生数学联赛,某中学先期举行选拔赛,根据初试成绩选出成绩优秀的20人进行复试.复试共设三道题,全部答对者获一等奖,答对两道者获二等奖,答对一道者获三等奖.已知某学生进入了复试,他在复试中前两题答对的概率均为a,第三题答对的概率为b若该生获得―等奖的概率为
,获得二等奖的概率为p,则p的最小值为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ca8b26c3ad6d892590290a2304126bd.png)
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解题方法
3 . 如图所示:在一个无限延展的平面上,铺满了边长为1的正方形网格.已知某质点从
出发,只能沿着网格线走,每次走一格,且每次向右走的概率为
,向上走的概率为
,向左走的概率为
,向下走的概率为
,且每一步之间相互独立.设按最短路径从
到达
的概率记为
,则当
取得最大值的时候
的取值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21198c85acf9672fafcfaa094de88342.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40b29d292eaa8743e4f534d4c85e999c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.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/19a0be4eebc5d70c51f72f28dbfc11e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19a0be4eebc5d70c51f72f28dbfc11e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
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解题方法
4 . 如图,有一张较大的矩形纸片
分别为AB,CD的中点,点
在
上,
.将矩形按图示方式折叠,使直线AB(被折起的部分)经过P点,记AB上与
点重合的点为
,折痕为
.过点
再折一条与BC平行的折痕
,并与折痕
交于点
,按上述方法多次折叠,
点的轨迹形成曲线
.曲线
在
点处的切线与AB交于点
,则
的面积的最小值为_________________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dcab46b9032d25a660af389a6a37210.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/192f4f9446c954a291f779d963f90257.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d71ba52c97faad3a085b9989969145.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d36626c9e45a25e8dc5bf4be4dbbfb3.png)
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2024-05-20更新
|
710次组卷
|
3卷引用:江西省南昌市2024届高三第二次模拟测试数学试题
23-24高二下·全国·课前预习
5 . 等差数列的前
项和公式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
已知量 | 首项、末项与项数 | 首项、公差与项数 |
求和公式 | ![]() | ![]() |
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6 . 不经过第四象限的直线
与函数
的图象从左往右依次交于三个不同的点
,
,
,且
,
,
成等差数列,则
的最小值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4c6592bbbee1498da630bd431299fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a3efb79f35db8448f3391252ab7d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8df332f01628130c084fd46aaca0a4b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/132668fc41c8266ba917dc5b4995c6b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79b752f0f189e5d8666daea73e145dff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e0a4d02005ed2c048b59856ad98c030.png)
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2024-05-14更新
|
220次组卷
|
2卷引用:江西省景德镇市2024届高三第三次质检数学试题
23-24高一下·全国·课前预习
7 . 已知向量
,
,
和实数λ,则:
(1)交换律:___________ ;
(2)数乘结合律:_______________ ;
(3)分配律:________________ .
注意:(1)向量的数量积不满足消去律;若
,
,
均为非零向量,且
,但得不到
.
(2)
,因为
,
是数量积,是实数,不是向量,所以
与向量
共线,
与向量
共线,因此,
在一般情况下不成立.
(3)推论:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
(1)交换律:
(2)数乘结合律:
(3)分配律:
注意:(1)向量的数量积不满足消去律;若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9dcf295c00ce5def2c8ac6ce4c937e5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4b7ca4667865ebe617fa6539e8d11fd.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8933b777306573e1f2c4d3dda8f5227d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/854e16eb319ee454088f5b527cf6c4d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15cd63a9494b3947c9ee121913d9f51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0795f64078d89a9f5cb3680bce2816b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380247c556e5174db9ea7e22ccd074b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b1c174ed96f1dd5043691210f155b5d.png)
(3)推论:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c340671538a445c23040ef2e1a802930.png)
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8 . 假设视网膜为一个平面,光在空气中不折射,眼球的成像原理为小孔成像. 思考如下成像原理: 如图,地面内有圆
,其圆心在线段
上,且与线段
交于不与
重合的点
,
地面,且
,
点为人眼所在处,视网膜平面与直线
垂直. 过
点作平面
平行于视网膜平面. 科学家已经证明,这种情况下圆
上任意一点到
点的直线与平面
交点的轨迹(令为曲线
)为椭圆或圆,且由于小孔成像,曲线
与圆
在视网膜平面上的影像是相似的,则当视网膜平面上的圆
的影像为圆时,圆
的半径
为____________ . 当圆
的半径
满足
时,视网膜平面上的圆
的影像的离心率的取值范围为____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e5c62f22d7afc5627fcb86599faa8e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/137d33c8575602cb3480ba3825dece9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a7442b64b37f685bc3ae88ff450c1a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70e92e4810c9461c39fae1acde95e489.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3dc6893e52bbca0d011ac46845334d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
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2024-05-09更新
|
99次组卷
|
2卷引用:四川省成都市实验外国语学校2023-2024学年高二上学期期末能力测评数学试题
解题方法
9 . 继淄博烧烤、哈尔滨冻梨后,最近天水麻辣烫又火了.据了解天水麻辣烫店内菜品一般由竹签串起成捆摆放,人们按照自己的喜好选好后递给老板,进行调制.某麻辣烫店内有西兰花、香菇、豆皮、海带、白菜等菜品,一游客打算从以上5种蔬菜中随机选择不同的3种,则西兰花和海带被选中的概率为___________ .
您最近一年使用:0次
23-24高一下·全国·课前预习
10 . 已知
,
,则:
(1)![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9e252f76824e2515fa7b951845da789.png)
__________ ,
__________ ,
即两个向量和(差)的坐标分别等于这两个向量相应坐标的和(差).
(2)若点A坐标为
,点B坐标为
,O为坐标原点,
则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75f051cabd248937ab69fce64a390920.png)
______ ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d5b06f57b825616050a9b897fb1a50b.png)
________ ,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ee2c8f08a2112767ba279bb135262f5.png)
_________ ,即一个向量的坐标等于表示此向量的有向线段的终点的坐标减去起点的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2c857eec21dd64ccf0ba530883bb6cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bcab0226effeccd2a336c23079bc1be.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9e252f76824e2515fa7b951845da789.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65de7c2f24ccd9a5a9b6c5920e981309.png)
即两个向量和(差)的坐标分别等于这两个向量相应坐标的和(差).
(2)若点A坐标为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56720e2f2b0ddd72156da495923698da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2852ae85cfcc804b3192ea8543c88938.png)
则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75f051cabd248937ab69fce64a390920.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d5b06f57b825616050a9b897fb1a50b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ee2c8f08a2112767ba279bb135262f5.png)
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