# IMOmath

We figured out you may have some general questions about math olympiads. Although this website is not affiliated with any math olympiad, and although we can’t provide official answers to any of the questions, we have very skillful and creative visitors who may be able to help. Of course, the validity of any advice you get from them (and us) is highly questionable.

Posted on: 02/03/2012 at 22:02:29     Posted by maticivan

Sir, I request you to post a pdf on the topic "Combinatorial Geometry".It would help a lot. Thanks, in advance.

Posted on: 06/05/2012 at 07:06:27     Posted by Dladem

about IMOSL $$2009/11$$ (see list of errors):

first, it seems to prove $$Q \ge m * 2^{m+2}.$$

So $$|F|> \sum F_i$$ meant we can’t equality (look to $$m=1$$ for a trivial observation for this).

hence we will have to make a stronger argument for this, anyone who can help to make this problem will be clear?

Posted on: 06/07/2012 at 13:06:43     Posted by Stijn C

Solve the equation f(1/x)+(1/x)f(-x)=x, where f is a real valued function defined for all real numbers except o.
First I replaced x by 1/x which made: f(x)+xf(-1/x)=1/x
Then I replaced x by -x, which made: f(-x)-xf(1/x)=-1/x

But now I don‘t understand how to solve to find f(x).

Thanks

Posted on: 01/29/2016 at 04:01:02     Posted by RaewynH11235

Prove that there are infinitely many positive integers $$n$$ such that $$n^{2} + 1$$ has a prime divisor greater than $$cn\log n$$ for some $$c> 0$$.