解题方法
1 . 对于有穷数列
,从数列
中选取第
项、第
项、
、第
项
,顺次排列构成数列
,其中
,则称新数列
为
的一个子列,称
各项之和为
的一个子列和.规定:数列
的任意一项都是
的子列.则数列
的所有子列和的和为__________ .
![](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/df5f59bc23cf55f56312c9ed9806371f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6af9e7b1c23db5584ad8521d4444d5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/608d034715f9b1dfb306f9c89d383582.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9e636879245230dd00a3ab3cbcfbfd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dcb1ddb73e4087f8cfcc40eead8b893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/533484c347e86e6bb635006a94530dc1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dcb1ddb73e4087f8cfcc40eead8b893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dcb1ddb73e4087f8cfcc40eead8b893.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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa301d4a86341fd749f1f8c72c970565.png)
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解题方法
2 . 若数列
满足
,
的前
项和为
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e77508401eb0f81e19ef3eb3444240c0.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/08eb71ecf8d733b6932f4680874dbbf3.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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解题方法
3 . 函数
与
的图象的交点个数是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74e7e79ac17c51c7a4aaf9d59ec9beb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21fbd1d0f09fae44dcaf6ace2fdaed0a.png)
A.2 | B.3 | C.4 | D.6 |
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解题方法
4 . 已知函数
,若
,则
的取值( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/324c31fdada4c31ce6107a2bc21760ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/147f89995c5aa07ce7f797c308c9c7d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/450398974b1561ca801e102e16df6789.png)
A.一定为正 | B.一定为负 | C.一定为零 | D.正、负、零都可能 |
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5 . 已知集合
,则“
”是“
”的( )条件.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56552cb9c94f329a295d508567103f75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f665ebe5fc0085518df777174d79410.png)
A.充分不必要 | B.必要不充分 | C.充要 | D.既不充分又不必要 |
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解题方法
6 . 已知函数
在区间
上单调递减,则实数
的取值范围是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56248f8876da343781c0021c6c75a30f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f114df5ceabdb7e5fd3fdad4eaf056.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 如图,一个正八面体的八个面分别标以数字1到8,任意抛掷一次这个正八面体,观察它与地面接触的面上的数字
,得到样本空间
,设事件
为奇数
,事件
,事件
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/311314491bc52778b4d1c1765894d0ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e171f08a189e8a75094dead09255738f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ca8bdc812627d925f00ed7c145d696.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94f8529f8e623e55061a44ff5d5050a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a0ace1a8c22a0e1de183642a54a0af5.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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8 . 某高校统计的连续5天入校参观的人数(单位:千人)如下:
并计算得,
.
(1)求
关于
的回归直线方程,并预测第10天入校参观的人数;
(2)已知该校开放1号,2号门供参观者进出,参观者从这两处门进校的概率相同,且从进校处的门离校的概率为
,从另一处门离校的概率为
.假设甲、乙两名参观者进出该校互不影响,已知甲、乙两名参观者从1号门离校,求他们从不同门进校的概率.
附:回归直线方程
,其中
.
样本号 | 1 | 2 | 3 | 4 | 5 |
第 | 1 | 2 | 3 | 4 | 5 |
参观人数 | 2.4 | 2.7 | 4.1 | 6.4 | 7.9 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/985f1673ddf7ed5872c91f01ba8eef01.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)已知该校开放1号,2号门供参观者进出,参观者从这两处门进校的概率相同,且从进校处的门离校的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
附:回归直线方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db6103cb0f1d2bd6b19235d53ee7e98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/446c21b8025405469a473aa0b32f9373.png)
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9 .
中,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abe89e08beb475318e0c7d5a87a8712f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7e4e3219e8964f05b817dbd060c3628.png)
A.54 | B.27 | C.9 | D.![]() |
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10 . 已知球的半径为1,其内接圆锥的高为
,则该圆锥的侧面积为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4b8503f4706b8321e4e79a87eadea84.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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