解题方法
1 . 设随机变量X的分布列为
(1)求常数a的值;
(2)求随机变量X的数学期望;
(3)求
和
.
X | ![]() | ![]() | ![]() | ![]() | 1 |
P | a | 2a | 3a | 4a | 5a |
(2)求随机变量X的数学期望;
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54d605e3b8da550b0fdb487bddf7222e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf1988831be694d6149496a61331dd01.png)
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2 . 已知函数
.
(1)当a=1时,求曲线
在点
处的切线方程;
(2)讨论函数
的单调性;
(3)若
的有三个零点,求a的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba17f18c17d3d9f4145022baeb5c72bb.png)
(1)当a=1时,求曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ea9824af71c9da5db5a00ec06063024.png)
(2)讨论函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
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解题方法
3 . 设复数
.
(1)在复平面内,复数
对应的点在第二象限,求a的取值范围;
(2)若
是纯虚数,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/510be896ab149d7454d2bfe928abf0cd.png)
(1)在复平面内,复数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e4e2b866b0043a32fc78326553841d3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d52e497aa7422819d873a7333891e86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d8b3f66119c2ce542984d12eb2b6b77.png)
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名校
4 . 南充市临江新区是2020年7月经四川省人民政府同意成立的四川省第三个省级新区.新区成立后不断推出优惠政策、细化服务、持续加大招商引资力度,吸引了多家企业入驻投资,某高新技术企业入驻该新区后新研发了一种电子产品,该电子产品由甲、乙两个电子元件构成,这两个电子元件在生产过程中的次品率分别为
,
,组装过程中不会造成电子元件的损坏,若有一个电子元件是次品,则该电子产品为次品不能正常工作,现安排质检员对这批产品一一检测,确保无任何一件次品流入市场.
(1)求任取一件产品为次品的概率;
(2)若质检员检测出一件次品,求该产品仅有一个电子元件是次品的概率;
(3)现有两种方案:
方案① 安排两个质检员先分别检测甲、乙这两个元件,次品不进入组装生产线;
方案② 安排一个质检员检测成品,一旦发现成品为次品,则需更换成品中的次品的电子元件,更换电子元件的费用为20元/个;
已知每个质检员每月的工资为4000元,该企业每月生产该产品件![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
件,请从企业获益的角度选择方案.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bfdaa01ae7652656f1f0ccad1a2149c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc4b4c648f682711076868368d377fc6.png)
(1)求任取一件产品为次品的概率;
(2)若质检员检测出一件次品,求该产品仅有一个电子元件是次品的概率;
(3)现有两种方案:
方案① 安排两个质检员先分别检测甲、乙这两个元件,次品不进入组装生产线;
方案② 安排一个质检员检测成品,一旦发现成品为次品,则需更换成品中的次品的电子元件,更换电子元件的费用为20元/个;
已知每个质检员每月的工资为4000元,该企业每月生产该产品件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/391bd47f0e344b04b4e68dd49820ad00.png)
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名校
5 . 已知
(其中
为自然对数的底数).
(1)当
时,求曲线
在点
处的切线方程;
(2)当
时,判断
是否存在极值,并说明理由;
(3)若对任意实数
,不等式
恒成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04d21bd20b782e1b1a030b04d8394fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66367f83e841caba04d29fceaa5cf4f7.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b4d795709b0abcf47bceec2250f2f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68c6b6a11760d0724b0b60e55970e229.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(3)若对任意实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9baa33e282d8b0b45c68b268ac610044.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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6 . 已知等差数列
前
项和为
,
,
.
(1)求数列
的通项公式及前
项和
;
(2)设
,求数列
前
项和
.
![](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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/315b41eeea0dbaa395af2474c4ba6acb.png)
(1)求数列
![](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)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14a0186a38c1200be0048f088108fea1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d51f9147b8265c0276c1f2c2659197.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbd85b79372dc6e596d465f738c3c300.png)
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名校
解题方法
7 . 已知数列
满足
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b25cb161785c91899b8a558ea468157d.png)
(1)求数列
的通项公式;
(2)设数列
的前
项和为
,若存在正整数
,使得
成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b25cb161785c91899b8a558ea468157d.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e673e123f467a6f41459f6acb499db7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/493f2319f98a4fba8a17a0db5667d33f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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8 . 某全国连锁咖啡店,男会员占60%,女会员占40%,现对会员进行服务质量满意度调查.根据调查结果得知,男会员对服务质量不满意的概率为
,女会员对服务质量不满意的概率为
.
(1)随机选取一名会员,求其对服务质量不满意的概率;
(2)从会员中随机抽取3人,记抽取的3人中,对服务质量不满意的人数为X,求X的分布列和数学期望.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e6486784415f3537c9a13556c05d893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69ee3c61d2298e75fc4f1643f8ebc2e4.png)
(1)随机选取一名会员,求其对服务质量不满意的概率;
(2)从会员中随机抽取3人,记抽取的3人中,对服务质量不满意的人数为X,求X的分布列和数学期望.
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名校
解题方法
9 . 如图,正三棱柱
内接于圆柱,圆柱底面半径为2,圆柱高为4.若
,
分别为
,
中点.
、
、
、
四点共面;
(2)若从圆柱中把该正三棱柱
挖掉,求剩余几何体的表面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若从圆柱中把该正三棱柱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
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