Very important

  • Thread starter vip89
  • Start date
  • #1
vip89
32
0
Very important...

Let R denote the set of real numbers. Find all nondecreasing continuous
functions g : R R such that

g(x+g(y))=g(g(x))+g(y) for all x,y∈R
 

Answers and Replies

  • #2
HallsofIvy
Science Advisor
Homework Helper
43,021
971
And why is that "very important"?
 
  • #3
tiny-tim
Science Advisor
Homework Helper
25,838
256
Looks monotonous to me … :rolleyes:
 
  • #4
vip89
32
0
Looks monotonous to me … :rolleyes:

I think u see it easy...

I read this problem in abook,and I liked it
so can you solve it?
 
  • #5
vip89
32
0
Looks monotonous to me … :rolleyes:

And why is that "very important"?


I read this problem in abook,and I liked it
so can you solve it?
 
  • #6
tiny-tim
Science Advisor
Homework Helper
25,838
256
Hi vip89! :smile:

Hint: try differentiating with respect to x, and y, separately. :smile:
 
  • #7
HallsofIvy
Science Advisor
Homework Helper
43,021
971
Oh, I see. That hint didn't seem to make much sense until I did!

(Funny how often that happens.)
 
  • #8
tiny-tim
Science Advisor
Homework Helper
25,838
256
Oh, I see. That hint didn't seem to make much sense until I did!

(Funny how often that happens.)

Oh my goodness! Does it work? :smile:

I didn't actually try it! :rolleyes:
 
  • #9
vip89
32
0
...

oh...I can't solve it.!
can u send me the answer??I need it quickly and there is no time to solve it because I have final exams


Thankx very much
 
  • #10
tiny-tim
Science Advisor
Homework Helper
25,838
256
… I have final exams

Hi vip89! :smile:

It's because you have final exams that you need to practise the technique …in case it comes up!

(and if it doesn't come up … why are you bothered? :rolleyes:)

So … differentiating with respect to x … what do you get? :smile:
 
  • #11
vip89
32
0
I have acomption with my friend ,who find the answer first
 
  • #12
Redbelly98
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
12,152
170
I am going to stay with the topic as given in the subject line here.

Why is the competition with your friend important?
 
  • #13
vip89
32
0
ok , it is not important
can u solve it ,pls??
 
  • #14
HallsofIvy
Science Advisor
Homework Helper
43,021
971
Wouldn't that be cheating?
 
  • #15
Redbelly98
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
12,152
170
ok , it is not important
can u solve it ,pls??

Actually no, I can't. But I do have some advice for you.

In this forum, you'll pretty much never get other people to solve entire problems for you. People like to see some attempt that you tried to solve it first. So far you haven't done that.

Did you try the suggestion from tiny-tim in message #6 ? If not, then try it. If you did try it then explain how far you got with it, or why you were unable to get very far with it, or just what you don't understand.

And lastly, welcome to physicsforums.com :smile:
 
  • #16
vip89
32
0
ok
I will try
and I want to say that is not cheating because It is not homework
 
  • #17
vip89
32
0
That is wt I did:
 

Attachments

  • pass11.JPG
    pass11.JPG
    30.1 KB · Views: 288
  • pass12.JPG
    pass12.JPG
    23.3 KB · Views: 296

Suggested for: Very important

  • Last Post
Replies
14
Views
1K
Replies
7
Views
535
Replies
5
Views
571
Replies
4
Views
475
Replies
19
Views
692
Replies
4
Views
392
Replies
12
Views
462
Replies
5
Views
535
Top