1 . 已知数列
的前
项和为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a717bebdf6ad7e11db845d5f58cec33.png)
(1)求数列
的通项公式![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)判断数列
是否是等差数列,若是,加以证明;若不是请说明理由;
(3)求
的最小值,并求
取最小值时
的值.
![](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/7a717bebdf6ad7e11db845d5f58cec33.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)判断数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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2 . 在校运动会上,只有甲、乙、丙三名同学参加铅球比赛,比赛成绩达到
以上(含
)的同学将获得优秀奖.为预测获得优秀奖的人数及冠军得主,收集了甲、乙、丙以往的比赛成绩,并整理得到如下数据(单位:
):
甲:
;
乙:
;
丙:
.
假设用频率估计概率,且甲、乙、丙的比赛成绩相互独立.
(1)估计甲在校运动会铅球比赛中获得优秀奖的概率;
(2)设
是甲、乙、丙在校运动会铅球比赛中获得优秀奖的总人数,求
的分布列和数学期望
;
(3)在校运动会铅球比赛中,甲、乙、丙谁获得冠军的概率估计值最大?(结论不要求证明)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90bbeb88466f25da82ee060774501475.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90bbeb88466f25da82ee060774501475.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e15e00f40396e914d1d9955bd7785f1f.png)
甲:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b5c2ebff997804ce8da464e9003f904.png)
乙:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bfe3af7c01ccb01341a765db6aa6631.png)
丙:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e72a33281f69adb17001e92ed19f1f5.png)
假设用频率估计概率,且甲、乙、丙的比赛成绩相互独立.
(1)估计甲在校运动会铅球比赛中获得优秀奖的概率;
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
(3)在校运动会铅球比赛中,甲、乙、丙谁获得冠军的概率估计值最大?(结论不要求证明)
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解题方法
3 . 在数列
中,已知
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c0eddd71d4fa6c78b1a410784bafb16.png)
(1)求
,
的值;
(2)是否存在实数
,使得数列
为等差数列?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6065aaa8f3f103d1bc960da8318ce35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c0eddd71d4fa6c78b1a410784bafb16.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
(2)是否存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e6224c0adf74d78a27ba6d4222840b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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4 . 已知等差数列
中,
,
.
(1)求这个数列的第
项;
(2)
和
是不是这个数列中的项?如果是,求出是第几项;如果不是,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6df1038200f2d97a52c716aab6c3bcb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/919f8ca81f48d968e0b4d88ec7a61eb3.png)
(1)求这个数列的第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e60696d1c681628c57bb2c7e9d1814.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ab66291ef17f0d1664cefd6f6bffd31.png)
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解题方法
5 . 已知某种药物对某种疾病地治愈率为
,现有甲、乙、丙、丁4个患有该病的患者服用了这种药物,观察其中有多少患者会被这种药物治愈.
(1)求出甲、乙、丙都被治愈而丁没被治愈的概率;
(2)设有
人被治愈,求
的分布列和数学期望.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
(1)求出甲、乙、丙都被治愈而丁没被治愈的概率;
(2)设有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
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名校
6 . 设
,
,已知![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c2531ddff4f2ea2b2c82def00968a34.png)
(1)求实数
的值;
(2)求
的值;
(3)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/288bb95d20715b7ceba23fc610d75bfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65a40142c84be68ee2918c3a8303388c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c2531ddff4f2ea2b2c82def00968a34.png)
(1)求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38d3e44224b7475cc9e3e9e19624caaa.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/900e692d22d85268c5b437444ace3dba.png)
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名校
解题方法
7 . 已知![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d65d7a9714360d0f2f9f0b1b898996a.png)
(1)求
的值;
(2)求
的值;
(3)求
的展开式中含
项的系数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d65d7a9714360d0f2f9f0b1b898996a.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f35f7dcce39f3d4dc6b7faf84dc1d0a1.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1c31afa3bd0d8005f4c8abbdbf620b3.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b18fe6deb803fc86211e00c5ee62e968.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3336c8ed5361c10c37300e41e03f9f2f.png)
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解题方法
8 . 已知椭圆
的长轴长是短轴长的2倍,点
在椭圆C上.
(1)求椭圆C的方程;
(2)过点
的任意直线与椭圆C交于 A、 B两点,设点A、B到直线
的距离分别为
,
若
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beff2c06f85011ebdeea93cb77cd6c60.png)
(1)求椭圆C的方程;
(2)过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f449cadb49859b80c31ef1f68bfe81b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eddb435f90eee67f95b27913ce93b36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/022e760e46e36d69a7bb4a91f8e62eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78c8c55557adc4b0bfde6f1d6d95e520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63e84ae7c96a58b9b78769ea16fef91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79b752f0f189e5d8666daea73e145dff.png)
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解题方法
9 . 在等差数列
中,已知![](https://staticzujuan.xkw.com/quesimg/Upload/formula/813273d04c20c459b17fb1e3fa610015.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c90282d4a37c9a20620d4bbb0c263cae.png)
(1)求数列
的通项公式;
(2)求
的值;
(3)
是不是数列
中的项?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/813273d04c20c459b17fb1e3fa610015.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c90282d4a37c9a20620d4bbb0c263cae.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681d2c881109c10aca287612a64312b1.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26d0be29ab21f96a34c4430f10505868.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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解题方法
10 . 已知数列
的前
项和
.
(1)求数列
的通项公式;
(2)求数列
的前
项和
的最大值.
![](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/8f05f6e0d9887cffd2c92598997c83b0.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)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)
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