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
2 . 已知函数
,
.
(1)当
时,求
的单调区间;
(2)当
时,记
的极小值点为
.
(ⅰ)证明:
存在唯一零点
;
(ⅱ)求证:
.
(参考数据:
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f385b23c5ed85f350ffa395cd860f58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22dd8b3dc4c609bab82d356a5cc2208d.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e10e1c43b86a8cd4360ca9b57232164.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79b752f0f189e5d8666daea73e145dff.png)
(ⅰ)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
(ⅱ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc0733cb65fb25e9096618fff3348.png)
(参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/697572b42c40f498ed398099c659df1f.png)
您最近一年使用:0次
2024-05-04更新
|
244次组卷
|
2卷引用:福建省厦门第一中学2023-2024学年高二下学期期中考试数学试卷
名校
解题方法
3 . 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)
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名校
4 . 已知曲线
在点
处的切线为
.
(1)求直线
的方程;
(2)证明:除点
外,曲线
在直线
的下方;
(3)设
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1026c00ff9d78946b4984d09de77995.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1f84134092f31767ff9f7e8200a79fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(1)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(2)证明:除点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caa83d5be9b28fcfce25c9bfca0d3d4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ab873c4173a3992c043fbf32cab4d8c.png)
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2024-04-26更新
|
1266次组卷
|
4卷引用:云南省开远市第一中学校2023-2024学年高二下学期期中考试数学试题
5 . 已知函数
.
(1)讨论
的单调性;
(2)证明:对于任意正整数
,都有
;
(3)设
,若
,
为曲线
的两个不同点,满足
,且
,使得曲线
在
处的切线与直线AB平行,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e890e47703867732e6cbabe0b992797b.png)
(1)讨论
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(2)证明:对于任意正整数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76723b3695d866921d5fbc39b75801bb.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac0946a190994c1a568c7db6520841d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c663466d641b5fdfef1e529d6c330ecf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/166afeb61d5a80366a8ae29c912cd644.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/951b05c96af4f7704de24ac541b3f172.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d41acc47493556617fe7b9e55093d10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91621e591e16f8eb1139bde61cf5eff7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/951b05c96af4f7704de24ac541b3f172.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72c22ba46a7c8b1320ba9a90afe5094d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8152c0ec3385924337832fad816f460c.png)
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名校
解题方法
6 . 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)
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2024高三·全国·专题练习
7 . 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
8 . 已知函数
(a为常数).
(1)求函数
的单调区间;
(2)若存在两个不相等的正数
,
满足
,求证:
.
(3)若
有两个零点
,
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efa8ea75ca2f775085b1838bef2c641d.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
(2)若存在两个不相等的正数
![](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/abf7c745cd02f4620a175cf00ec85e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df3da00fe1feafb42d7e2254dd5f8589.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
![](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/40c67a34394380636fdf4b882ce28d40.png)
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2023-12-30更新
|
1206次组卷
|
10卷引用:5.3 导数在研究函数中的应用(练习)-高二数学同步精品课堂(苏教版2019选择性必修第一册)
(已下线)5.3 导数在研究函数中的应用(练习)-高二数学同步精品课堂(苏教版2019选择性必修第一册)(已下线)模块五 专题6 全真拔高模拟6黑龙江省哈尔滨市第六中学校2022-2023学年高三上学期期中数学试题福建省宁德市福安市福安一中2023-2024学年高三上学期10月月考数学试题(已下线)模块三 大招24 对数平均不等式(已下线)模块三 大招10 对数平均不等式重庆缙云教育联盟2024届高三高考第一次诊断性检测数学试卷(已下线)模块2专题7 对数均值不等式 巧妙解决双变量练(已下线)专题6 导数与零点偏移【练】(已下线)专题16 对数平均不等式及其应用【讲】
名校
解题方法
9 . 已知函数
,
.
(1)若函数
在R上单调递减,求a的取值范围;
(2)已知
,
,
,
,求证:
;
(3)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d013335d41c7a1e51b381eb8e7ef977.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22dd8b3dc4c609bab82d356a5cc2208d.png)
(1)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/111870a9ef48f1bb2797ae8f1825a8f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fde64f4d3c38e43fbdee24eadc4b0dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9897559d21ef1971f497be4269b107aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0527a896aec4a245945e5edee00deed.png)
(3)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64f6bf190c55c3a0ddbca2ff7a5ecf42.png)
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2023-12-30更新
|
1112次组卷
|
3卷引用:吉林省通化市梅河口市第五中学2023-2024学年高二下学期第一次月考数学试题
名校
10 . 已知
.
(1)求函数
的单调区间和极值;
(2)请严格证明曲线
有唯一交点;
(3)对于常数
,若直线
和曲线
共有三个不同交点
,其中
,求证:
成等比数列.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/647014ad8af603468f4100043c4bde15.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/720777756eaef6fd797e16c7656bd916.png)
(2)请严格证明曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/720777756eaef6fd797e16c7656bd916.png)
(3)对于常数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3387f1c69de6c2407212536b35150e5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46111e4d12c21798aa213c0d7804c2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/720777756eaef6fd797e16c7656bd916.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3059524807d8e93433b8d994df6ede70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1310a7a80d1f8751a3f8cafe7f8c8b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad7169ce3255d2a02a20aa5932d2bd48.png)
您最近一年使用:0次
2023-12-19更新
|
632次组卷
|
3卷引用:广东省广州市第二中学2023-2024学年高二下学期期中考试数学试题