Forgot password
 Register account
View 340|Reply 7

[函数] 导数

[Copy link]

186

Threads

206

Posts

0

Reputation

Show all posts

guanmo1 posted 2023-4-17 19:59 |Read mode
Last edited by hbghlyj 2025-3-19 08:21$f(x)=(x-a)^3(x-b)$,且 $w=\frac{f(x)-f(k)}{x-k}$ 在 $(0,+\infty)$ 上严格单增,$k \inZ$,求 $\frac{b}{a}$ 的取值范围.

186

Threads

206

Posts

0

Reputation

Show all posts

original poster guanmo1 posted 2023-4-18 12:44
没大佬解答啊?

186

Threads

206

Posts

0

Reputation

Show all posts

original poster guanmo1 posted 2023-4-19 20:22 from mobile
顶一下

48

Threads

771

Posts

93

Reputation

Show all posts

Czhang271828 posted 2023-4-21 14:11
Last edited by Czhang271828 2023-4-23 13:19原答案乱写的, 请移步

zhuanlan.zhihu.com/p/621740738

764

Threads

4672

Posts

27

Reputation

Show all posts

isee posted 2023-4-22 00:27
Last edited by isee 2023-5-25 23:11
Czhang271828 发表于 2023-4-21 14:11
$w'(x)$ 是个非零多项式函数, 从而零点离散. 故 $w(x)$ 在 $x> 0$ 严格单调递增等价于 $w'(x)\geq 0$. 算 ...
我见到了类似的,2023届上海浦东二模第12题:

shshpdpd12.png

此楼限制下的标答为 (1,3],网上解析好像用了(实质上) 函数的凹凸性
isee=freeMaths@知乎

48

Threads

771

Posts

93

Reputation

Show all posts

Czhang271828 posted 2023-4-22 13:05
isee 发表于 2023-4-22 00:27
我见到了类似的,2023届上海浦东二模第12题:


可以贴一个标答吗? 我用 chatGPT 算的, 估计哪里有错...

Comment

没过程  posted 2023-4-22 20:27

764

Threads

4672

Posts

27

Reputation

Show all posts

isee posted 2023-4-22 23:11
Czhang271828 发表于 2023-4-22 13:05
可以贴一个标答吗? 我用 chatGPT 算的, 估计哪里有错...
知乎上有个过程:zhuanlan.zhihu.com/p/621740738
isee=freeMaths@知乎

Quick Reply

Advanced Mode
B Color Image Link Quote Code Smilies
You have to log in before you can reply Login | Register account

$\LaTeX$ formula tutorial

Mobile version

2025-7-15 14:50 GMT+8

Powered by Discuz!

Processed in 0.014932 seconds, 30 queries