STEP ii 2007 Q2

Hi all ---

About STEP II 2007 Q2, I don't know if I'm just missing this --- but Chewwy's solution --- http://www.thestudentroom.co.uk/attachment.php?attachmentid=43612&d=1187998514 --- implies $q > p$. The post is at http://www.thestudentroom.co.uk/showthread.php?t=443433&page=3&p=9663502#post9663502.

The actual question:

$y = 2x^3 - bx^2 + cx$ has a maximum point at $(p,m)$ and a minimum point at $(q,n)$ where . Let $R$ be the region enclosed by the curve, the line $x = p$ and the line $y = n$.

Now, the question gives $p > 0$.

But how do we know $q > p$?

And how do we know $q > 0$?

Thank you ---