名校
解题方法
1 . 已知
,
,且
在点
处的切线与直线
垂直.
(1)求实数
的值.
(2)若
的图象经过原点,且
,当
时,
过点
的切线至少有
条,求实数
的取值范围.
(3)若
,且
,其中
,
均为正实数.证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2dc19a078760863c7e681e59e0ec56b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c8bb7e252de0e54ca82ad2c36ffba37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5828873f8369183faf71181cda5b61d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/227d4946b9dbfdc8bef33b42b6a82572.png)
(1)求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46be55c8f2760d6db125f46691a3de48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbab1a525c4451a43041defaa18a98f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d9fab43d7bc79776880a47091152b46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46be55c8f2760d6db125f46691a3de48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa70fa7eb86c3733e2c1f1c7d07dd802.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7892b90ae2ff71fd827c95e5aabc3049.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ca96bf407a3ba46ef3c59c5eee4137c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/803b13fac1480b428cb4ee4555852024.png)
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2 . 已知![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c3876a78d1c0f3b0eb07825c34d1a5d.png)
(1)若
,过点
作曲线
的切线l,求切线l的方程;
(2)若
,
是函数
的两个不同的极值点,求证:
;
(3)
时,
对
恒成立,证明不等式
对任意的正整数n都成立.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c3876a78d1c0f3b0eb07825c34d1a5d.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5c10f14aae6fb21e047ecb39cdf40c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/051c9ada827d18c8377743299d3761df.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b108ab31cc093f03cf48ad65429889e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb9374a0245ffdcb4b23bd8bd5b662a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bad5c8a4e4bad474651c0a61de820ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fada3f2d5821bea73b3f22b25a07a8a7.png)
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名校
3 . 某学校在高一、高二年级学生中各随机选取40名学生进行“新冠病毒防控”的知识竞赛.对两个年级的成绩进行分析处理,得到高一年级成绩的频率分布直方图和高二年级成绩.
![](https://img.xkw.com/dksih/QBM/2021/6/19/2746096248406016/2768569421570048/STEM/48a5a0651b5f437f921efd319b5cadd8.png?resizew=230)
![](https://img.xkw.com/dksih/QBM/2021/6/19/2746096248406016/2768569421570048/STEM/eec31f81695541aeaf77ce28b0ae2d26.png?resizew=162)
(1)求频率分布直方图和频数分布表中未知量m,t的值;
(2)规定成绩不低于90分为“优秀”,分别求高一、高二年级选取的40人中优秀的学生人数,若在这些优秀学生中按年级用分层抽样的方法抽取6人,高一、高二年级各自抽取多少人;
(3)在(2)分层抽样抽取的6名优秀生中任意选取2人,求高一、高二各有一名学生的概率.(用列举法解答)
![](https://img.xkw.com/dksih/QBM/2021/6/19/2746096248406016/2768569421570048/STEM/48a5a0651b5f437f921efd319b5cadd8.png?resizew=230)
![](https://img.xkw.com/dksih/QBM/2021/6/19/2746096248406016/2768569421570048/STEM/eec31f81695541aeaf77ce28b0ae2d26.png?resizew=162)
高一 高二
(1)求频率分布直方图和频数分布表中未知量m,t的值;
(2)规定成绩不低于90分为“优秀”,分别求高一、高二年级选取的40人中优秀的学生人数,若在这些优秀学生中按年级用分层抽样的方法抽取6人,高一、高二年级各自抽取多少人;
(3)在(2)分层抽样抽取的6名优秀生中任意选取2人,求高一、高二各有一名学生的概率.(用列举法解答)
您最近一年使用:0次