Suppose you know that f(x) is an odd function on the domain of all real numbers and that the function is concave up on the intervals 0

Question

Suppose you know that f(x) is an odd function on the domain of all real numbers and that the function is concave up on the intervals 0<x<3 and 5<x and concave down on the interval 3<x<5. 
List ALL intervals on which the function f(x) is concave up and ALL intervals on which the function f(x) is concave down; explain how you know these to be correct.

anonymous · Answer

Are you sure about the phrasing of your question? You're explicitly told the intervals and concavity of $f$. Did you mean increasing/decreasing?

anonymous · Answer

Is this really just a bad question? Because I copied it word for word

anonymous · Answer

The question asks for intervals of concavity, but gives you just that.

If that's what it says, maybe you're missing some minor but significant notation. It could be that you're given the intervals of concavity for the derivative $f'$, and you need to use that to determine the concavity of $f$, or vice versa.