1 . “杨辉三角”是二项式系数在三角形中的一种几何排列.从第1行开始,第n行从左到右的数字之和记为
,如
,
,…,
的前n项和记为
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e7df0430db8db9fc354ffdd038fb432.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c996a43ff8843aec0be0a9d0ac0e9ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
A.在“杨辉三角”第10行中,从左到右第8个数字是120 |
B.![]() |
C.在“杨辉三角”中,从第2行开始到第n行,每一行从左到右的第3个数字之和为![]() |
D.![]() ![]() |
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2 . 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.若要求质点按最短路径从
到达
,则可能的不同路径有__________ 条(用数字作答);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/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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3 . 已知集合
,
,则
的子集的个数是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01113d5534c82b64a2def109eb84c770.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661e76fe4f64296149495560eaaba6ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fdbfa7a63fdf5717d40c8c9a73ec160.png)
A.2 | B.4 | C.8 | D.16 |
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4 . 若
则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c92cdb1594134804bb0ee22c723604e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/934ef6bd04727a99b37e6f94c767d782.png)
A.![]() | B.![]() | C.9 | D.63 |
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5 . 已知集合
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c48164a83670a42aff4afa5b3750d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5377eff9996bfc6da27ddbed01627307.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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6 . 设
是一个无穷数列
的前
项和,若一个数列满足对任意的正整数
,不等式
恒成立,则称数列
为和谐数列.关于命题:①若等差数列
为和谐数列,则
一定存在最小值;②若
的首项小于零,则一定存在公比为负数的一个等比数列为和谐数列.下列判断正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edefd533852c96d0d8047c859d4bc458.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
A.①和②都为真命题 | B.①和②都为假命题 |
C.①为真命题,②为假命题 | D.①为假命题,②为真命题 |
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7 . 化循环小数为分数:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1614b07a69a5c23ef6902a2770569c6.png)
___________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1614b07a69a5c23ef6902a2770569c6.png)
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8 . 甲、乙、丙、丁四人相互做传球训练,第1次由甲将球传出,每次传球时,传球者都等可能地将球传给另外三个人中的任何一个人.则4次传球的不同方法总数为_________ (用数字作答);4次传球后球在甲手中的概率为_________ .
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9 . 已知
中,角
所对的边分别为
的面积记为
,若
,则( )
![](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/718b5b48053888ab3b234b8cb56a0fc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d6dae531265e6d528cbf1346e41aca.png)
A.![]() |
B.![]() ![]() |
C.![]() ![]() |
D.若![]() ![]() ![]() ![]() |
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10 . 已知全集
,集合
,若
有4个子集,且
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62b68095137c7e5a3e90af74b515d33f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db5c5c7e2b86320b6d4204815f685ce3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c093cbde3d3472d1f7f2b0dff2bc4881.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dea9a4259cca10c1f5af28e621ebafd6.png)
A.![]() | B.集合![]() |
C.![]() | D.![]() |
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