1 . 定义:若数列
满足所有的项均由
,1构成且其中
有
个,1有
个
,则称
为“
数列”.
(1)
,
,
为“
数列”
中的任意三项,则使得
的取法有多少种?
(2)
,
,
为“
数列”
中的任意三项,则存在多少正整数对
使得
,且
的概率为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9e50500c867549419124bb1be66b5ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da306eabdc0551d7bfe871b8f6251eb4.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb853c35a7d17396aa032e33505002f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e17ef2c7384f5b6b642dffd0eb2c890.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bd88e6f1b20eb0c484882f051b0cf43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51ce2b0d668aa3784cf88a0dc398d2b9.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb853c35a7d17396aa032e33505002f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e17ef2c7384f5b6b642dffd0eb2c890.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da306eabdc0551d7bfe871b8f6251eb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31d496307b8bab026701a3293ccde58a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc81b7ec873c104329e5b36aa5255088.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51ce2b0d668aa3784cf88a0dc398d2b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
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2 . 数学老师给小明布置了10道数学题,要求小明按照序号从小到大的顺序,每天至少完成一道,如果时间允许,也可以多做,甚至在一天全部做完,则小明不同的完成方法种数为
A.55 | B.90 | C.425 | D.512 |
您最近一年使用:0次
2018-05-03更新
|
1315次组卷
|
3卷引用:【全国区级联考】北京市海淀区2017-2018学年高二第二学期期中练习数学(理)试题
名校
3 . 现有12张不同的卡片,其中红色、黄色、蓝色、绿色卡片各3张,从中任取3张,要求这3张卡片不能是同一种颜色,且红色卡片至多1张,不同取法的种数为__________ .
您最近一年使用:0次
2017-05-03更新
|
900次组卷
|
5卷引用:山东省德州市2017届高三下学期4月二模考试数学(理)试题