1 . 我们知道,在平面内取定单位正交基底建立坐标系后,任意一个平面向量,都可以用二元有序实数对
表示.平面向量又称为二维向量.一般地,n元有序实数组
称为n维向量,它是二维向量的推广.类似二维向量,对于n维向量,也可定义两个向量的数量积、向量的长度(模)等:设
,
,则
;
.已知向量
满足
,向量
满足
.
(1)求
的值;
(2)若
,其中
,当
且
时,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39c2af42141367e6e9ff0296c31daa7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62b3b354facacd72bc68da6ac07be453.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48d974578eb15ca117e0cb1b59788d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99aa60676891adca75eac086182a15c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2581496116ddfba6dd03722fd771d5a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5babafd9f4e5c3c222ba25a3de66794.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a48d974578eb15ca117e0cb1b59788d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7cb2f5c0569962cd7c1026f388cb661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99aa60676891adca75eac086182a15c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4492fb816272cd60cf3456c6a064020e.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efa3e5481ce1f11ea4cb1d1ddc71413.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/301fa5679316c282923735aff9285559.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95ac252e9126ab540c0102b941f0ee42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74cac554f22f3655ef6691b2ef821eac.png)
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2 . 随着牡丹花期结束,曹州牡丹园为了更好地了解游客需求,优化自身服务,提高游客满意度,随机对200位游客进行了满意度调查,其中100位男性中有86位满意;100位女性中有94位满意:
(1)根据小概率值
的独立性检验,能否推断游客对该牡丹园的满意度与性别有关;
(2)若用频率估计概率,从该牡丹园的游客中随机选取3人,设3人中满意的人数为X,求X的分布列和数学期望.
附:
,
.
(1)根据小概率值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0298d106f2b72aadf3cffce041a25da6.png)
(2)若用频率估计概率,从该牡丹园的游客中随机选取3人,设3人中满意的人数为X,求X的分布列和数学期望.
附:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2187714e660234f0b72f2b47d3ea685a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/356b05e46b10ee51c3e43546d73ec96c.png)
0.1 | 0.05 | 0.01 | |
2.706 | 3.841 | 6.635 |
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3 . 若数列
满足
,则称数列
为牛顿数列,若
,数列
为牛顿数列,且
,
,数列
的前n项和为
,则满足
的最大正整数
的值为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33610d2a46105e3c8456257221d3d07b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b1c079afd1b058adc67a50f48f3d466.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/195fc747e2fc50cb6df2c844d51e4d80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be3bb631154bd03c814e8f6c0b39ea8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/753cd148252b19cf3a164d6a15fa90c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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4 . 已知
的展开式中所有项的系数的和为1,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a353236f25792c996986eefb149af507.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380bbacf854e30e2e747fc286d2b9997.png)
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5 . 设
,
在
方向上的投影向量为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0ee058d80bf1f695e71ad49beb81f81.png)
________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3391576038a1782ce7283ddb46e6ef7.png)
![](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/81cdfd82868aefda05f52913dfd762a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0ee058d80bf1f695e71ad49beb81f81.png)
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6 . 已知变量x,y之间的一组相关数据如下表所示:
据此得到变量x,y之间的线性回归方程为
,则下列说法正确的是( )
x | 2 | 4 | 6 | 8 | 10 |
y | 1 | 1.6 | 2 | a | 3 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc78bd8b336a55d5bb07745972f2c417.png)
A.变量x,y之间成正相关关系 | B.当![]() ![]() |
C.![]() | D.可以预测,当![]() ![]() |
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7 . 已知菏泽市某公司生产的一袋牡丹花茶的重量X(单位:克)服从正态分布
,其中
的产品为“合格品”,则从这些牡丹花茶中随机抽取一袋,则抽到合格品的概率约为( )
(附:若随机变量X服从正态分布
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33b7e213de8ac3aa1e54809eb5a058d7.png)
,
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a00ddb60174f635fa8a5f7ab8b8a1cb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f45684273f461a8593e1419288d18e6d.png)
(附:若随机变量X服从正态分布
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29bcc248a7770a16fa10fc4602d71e0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33b7e213de8ac3aa1e54809eb5a058d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d52d950447e4b001cef54848142ab7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcaae0a2d9389a9cfbe0aad5cbdf1eed.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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8 . 已知函数
为偶函数,当
时,
,且
,则实数a的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e0248d29f03e759f957da3012162cc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36f247866d4020ed309d4e4d121ce445.png)
A.1 | B.10 | C.100 | D.1000 |
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9 . 已知角
的顶点与原点重合,始边与x轴的非负半轴重合,终边经过点
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e14bb4ae223d1c251c33daca9649824.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c8542ba931b2720ee7440f2054b8394.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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10 . 已知等比数列
的前n项和为
,
,
,则
( )
![](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/d5ef35b21da4cd8130642539d8245f83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4fb4b599e37a825bce2a0c29f09af8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/614306cc3f34bdee4d5d885b79667645.png)
A.62 | B.50 | C.40 | D.22 |
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