1 . 对于三次函数
,现给出定义: 设
是函数
的 导数,
是
的导数,若方程
有实数解
,则称点
为函 数
的 “拐点”. 经过探究发现: 任何一个三次函数都 有 “拐点”,任何一个三次函数都有对称中心,且 “拐点” 就是对称中心. 已知函数
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6f7eea22322f9e1695c0e77c773401a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e307e47c0759153103f81ac8e1f0a9a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f6bfdb24ecf5da863405c2b40936ff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15bf2eae9b50e554fb4768f81322c23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e307e47c0759153103f81ac8e1f0a9a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7894fb445b2a499d419b17a28ed6e85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5cbf1211335bcbc0ebb05414669eda0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1121ec4e8252f7b9cbeda63e84072b89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6f7eea22322f9e1695c0e77c773401a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ef06087f0086b408a37ac079f04fea.png)
A.函数 ![]() |
B.函数 ![]() |
C.点 ![]() ![]() |
D.方程 ![]() |
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2 . 若函数
在点
处的切线的斜率为1,则
的最小值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c89b2ecfced2e74f5be44e49da3a8a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/811508165a0f0cf31a69c555e0b4ab57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f7266b2ef457b8ddeee3fa2cc24022e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
3 . 记
为等差数列
的前
项和,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29518f13a1ebc3fff8181c2d7cfba22f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8150f65410c124ec09b0b21f9f9cb71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d07286357b06a17772042c72b994d98.png)
A.2 | B.3 | C.10 | D.4 |
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解题方法
4 . 已知数列
的通项公式为
,前
项积为
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1185cac997f45b202c8bf9a33d8186.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
A.在数列![]() ![]() | B.在数列![]() ![]() |
C.数列![]() | D.使![]() ![]() |
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解题方法
5 . 已知点
为椭圆
上任一点,椭圆的短轴长为
,离心率为
.
(1)求椭圆
的标准方程;
(2)若点
是抛物线
的准线上的任意一点,以
为直径的圆过原点
,试判断
是否为定值? 若是,请求出这个定值; 若不是,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/014b99f5c93a4ce8cd6251c12c1d1b37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91edc7e2d4811f5ea6c01284cf00393a.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4ea998b0d4284e05684a27fd1cca7ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3eeae1143162b4d564f4b77e3f77cd8.png)
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6 . 如图,在斜三棱柱
中,
分别是
的中点.
平面
;
(2)若
,且
,求直线
与平面
所成角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed1db08240a186b4b563c0e3e3dfd99d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9cfe81171fa15f47d81ca8bd4369234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6748d9b9948485c5ba87ca8751c6e053.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88e0feac3ad1bef70d1849e6abb91bb2.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63c336cb7a3eec081f1de84c1de782db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90b92c6f2f64bb2768f518cab73483b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15e58659e6ee4d93650e2edb6d6f7ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
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7 . 若等比数列
的各项均为正数,且
成等差数列,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29518f13a1ebc3fff8181c2d7cfba22f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94f53b1caa283934f588df7c65d0794.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d199ca00db1ece6be9e802a22dfc0f44.png)
A.3 | B.6 | C.9 | D.18 |
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8 . 某家会员足够多的知名水果店根据人的年龄段办理会员卡, “年龄在 20岁到34岁之间的会员” 为 1 号会员,占比 20%, “年龄在 35 岁到 59 岁之间的会员” 为 2 号会员,占比
,“年龄在 60 岁到 80 岁之间的会员” 为 3 号会员,占比
,现对会员进行水果质量满意度调查. 根据调查结果得知,1 号会员对水果质量满意的概率为
号会员对水果质量满意的概率为
号会员对水果质量满意的概率为
.
(1)随机选取 1 名会员, 求其对水果质量满意的概率;
(2)从会员中随机抽取 2 人,记抽取的 2 人中,对水果质量满意的人数为
,求
的 分布列和数学期望.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bffe08bd9189a9b41a9bf55137fdbf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee6dc6cf991200a495e96d643749054d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7209b12ed2e7f469ee5aa4af5e487e99.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0a99303fbb20c35bbdef5eb7f63972c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d0e7bfbd56fe73dfe04c04da749d942.png)
(1)随机选取 1 名会员, 求其对水果质量满意的概率;
(2)从会员中随机抽取 2 人,记抽取的 2 人中,对水果质量满意的人数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
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解题方法
9 . 若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e795ff2442fc5ed6c744ce499c834518.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ffb5b54097f709bb9a58f149cd19160.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7c4040c0e4a1931ac86efa405979298.png)
A.![]() | B.1 | C.64 | D.0 |
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10 . 在
的展开式中,常数项为_________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6336bf2216ed0b079152d4ccca5b8bd6.png)
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