名校
解题方法
1 . 已知函数
.
(1)证明:
;
(2)设函数
,若
恒成立,求
的最小值;
(3)若方程
有两个不相等的实根
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc36a3c21811a9754a537062a73f43e6.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e799e937076aa5a7dcd51cdc0f40f6b0.png)
(2)设函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5706e65074de43ba1d3b0f5861646e1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa18838a13fda4e45612c32cdf98b71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
(3)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9c0d827ef8598ba6b70b34b2bdcd1e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce7ae90d808f05e86ea063238e4b2f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f98def21c9ea5780553a3dfb46d455f.png)
您最近一年使用:0次
名校
解题方法
2 . 设实系数一元二次方程
①,有两根
,
则方程可变形为
,展开得
②,
比较①②可以得到![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e360b7ba27dfc3e5d401027d5bd8a5.png)
这表明,任何一个一元二次方程的根与系数的关系为:两个根的和等于一次项系数与二次项系数的比的相反数,两个根的积等于常数项与二次项系数的比.这就是我们熟知的一元二次方程的韦达定理.
事实上,与二次方程类似,一元三次方程也有韦达定理.
设方程
有三个根
,则有
③
(1)证明公式③,即一元三次方程的韦达定理;
(2)已知函数
恰有两个零点.
(i)求证:
的其中一个零点大于0,另一个零点大于
且小于0;
(ii)求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c3f3db6b7c682450309a6ccba5ac5a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce7ae90d808f05e86ea063238e4b2f9.png)
则方程可变形为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/455d33fcfd9a59d6b374e9d25888cd2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e42b42152492cbdfec62c7a02be4055.png)
比较①②可以得到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e360b7ba27dfc3e5d401027d5bd8a5.png)
这表明,任何一个一元二次方程的根与系数的关系为:两个根的和等于一次项系数与二次项系数的比的相反数,两个根的积等于常数项与二次项系数的比.这就是我们熟知的一元二次方程的韦达定理.
事实上,与二次方程类似,一元三次方程也有韦达定理.
设方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ddc5e3c2c7c6f4d2d0ab396b65679a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05b8ec9d4206ea66a02de5c4a1e1e911.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb8d75a2417827b2c5b09ba9385fe252.png)
(1)证明公式③,即一元三次方程的韦达定理;
(2)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2b5e4746c2bd0afb279630698afd3a0.png)
(i)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
(ii)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20d6fc9b90f370fbb27552876b650f8f.png)
您最近一年使用:0次
2024高三·全国·专题练习
3 . 已知
,函数
有两个零点,记为
,
.
(1)证明:
.
(2)对于
,若存在
,使得
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/655c46b33730f3a29b9ec3024df71375.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17de16980dc347680c23b17153ef1232.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3282e5fde4ae53fcb1bb072a685304c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2aba77b36579eeccb98cdc308ce92bc8.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc043d78e4c9ad2281754d6c1cac8791.png)
(2)对于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eedf333393bdf56f8b428e9a7d2eb3de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7443588709e037203d0962bc5b3c705.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c403614594d401cf38ebc4d48c2f47f3.png)
您最近一年使用:0次
名校
解题方法
4 . 已知
,
.
(1)求
在
上的最小值;
(2)求曲线
在
处的切线方程
,并证明:
,都有
;
(3)若方程
有两个不相等的实数根
,
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9b6a91900d0dfa6296cdee22fdd6fe6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac4cbc7b067862a3d9c6789b392fc068.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea17ec8f211e8be2571fbcce23e04eb8.png)
(2)求曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b23a03ca8f1729bfcadf513784817fc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3add1679c27392a1a7f635723a4b36eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa18838a13fda4e45612c32cdf98b71.png)
(3)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/338316b0fe50fdea0f2f75aec4c990dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffd888afdcfdb3e91a157d50f65e915e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8013645996eb5766aaf7de48d243d1de.png)
您最近一年使用:0次
2024高三·全国·专题练习
解题方法
5 . 已知函数
.
(1)证明:
;
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e500179a7ac958616cd7dfa1dd8ca147.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9c599e8d420006448905acec2b8234.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb1c49cf303d162268d58500834887e1.png)
您最近一年使用:0次
2024高三·全国·专题练习
解题方法
6 . 已知函数
.
(1)证明:当
时,
;
(2)当
时,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eb89f876ec063673730aa225074b273.png)
(1)证明:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/576a9bd59c45f48818ef16d33f71bb91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebfdecc7f8089cb23c20d0a93ee1b601.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09881de0dc186bbcd1e60eb00159ee97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b76f5ea1a1281631da9f5c48afe23377.png)
您最近一年使用:0次
名校
7 . 已知
,
是
的导函数,其中
.
(1)讨论函数
的单调性;
(2)设
,
与x轴负半轴的交点为点P,
在点P处的切线方程为
.
①求证:对于任意的实数x,都有
;
②若关于x的方程
有两个实数根
,且
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42fe84ecdcafb66c2e3a4dd702503729.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/724340d69477c0ec2418c392b22b1cab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10bbdef421c976962a270a2beabbad91.png)
(1)讨论函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/724340d69477c0ec2418c392b22b1cab.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5662583ace896ce1f779eaba4911f156.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f786a5701dc1a8a015e8843c3360151b.png)
①求证:对于任意的实数x,都有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5207aa3a627a574a1e12ae87dd609fdb.png)
②若关于x的方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1083654e970df6adf6e1c5967501e80c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce7ae90d808f05e86ea063238e4b2f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26d8dafc71b106f39f4e15442220897b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee624bd3ec8c33ac93551432b739af17.png)
您最近一年使用:0次
名校
8 . 已知函数
,曲线
在点
处的切线为
.
(1)求
的方程;
(2)判断曲线
与直线
的公共点个数,并证明;
(3)若
,令
,求证:对任意的
,都有
成立.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d47bdd7fa866c56bf4fc60ad7f369db4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c9f8845aa2b51c460f2d798c9f62fa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(2)判断曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b4d795709b0abcf47bceec2250f2f9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3682822ac42a9c9196109af27044b88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9d1d8e655e9989b888fbab8099690eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852913f3c6048e49f9ccd2b6fee57eda.png)
您最近一年使用:0次
名校
解题方法
9 . 已知函数
,
.
(1)当
时,求证:
;
(2)当
时,
恒成立,求实数
的取值范围;
(3)已知
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6b1868d9850b7103e1326eb001dfbce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9100abe06c208f6742dc75861a33989.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa18838a13fda4e45612c32cdf98b71.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adc3e5be1796493161a4df7e28a6f6b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa18838a13fda4e45612c32cdf98b71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(3)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2aa78c96db411c9e1e939ae16de78d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d062874efc06af87693c548b09fbc91.png)
您最近一年使用:0次
2023-11-30更新
|
428次组卷
|
3卷引用:江苏省镇江市扬中高级中学2024届高三上学期十月学情检测数学试题
解题方法
10 . 已知函数
.
(1)证明不等式:
,
;
(2)若
,
,使得
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02e41217f3039effba4b352e7ae68deb.png)
(1)证明不等式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a623d70dccf0773e19310b4cc863fbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac4cbc7b067862a3d9c6789b392fc068.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9be23b1d40d59f429f2f90c814815491.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33bd24e647a626899a243a3f3984f90a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cd6f48770212bd0382da5dbab6d95c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d136fd3c66c833cc3cf80cbf0b2870b1.png)
您最近一年使用:0次
2022-12-09更新
|
331次组卷
|
2卷引用:广西贵港市2023届高三毕业班上学期12月模拟考试数学(理)试题