Date: Dec 3, 2012 11:08 AM Author: Jose Carlos Santos Subject: Re: Unbounded second derivative On 03-12-2012 11:17, JosÃ© Carlos Santos wrote:

> This is probably very simple, but I can't see it. :-) Let f be a twice

> derivable function from [0,+oo[ into R such that:

>

> 1) lim_{x to +oo} f(x) = 0;

>

> 2) lim_{x to +oo} f'(x) does not exist.

>

> Prove that the function f'' is unbounded.

Forget it! I've done it.

Best regards,

Jose Carlos Santos