What is Q?
(You cetainly do not mean the Q continuum).
I assume that you want to know for which value of x has the angle a maximum.
From your sketch you see:
You'll get an extremum if the first derivative of this function equals zero:
After a few and simple transformations you'll get:
That means: . Solve for x. I've got:
There is of course a negative solution of x but thisvalue isn't very realistic with your problem.
maybe this will help a little bit further: In this forum you can find a link to the LaTeX-tutorial.
(If I find the link in time I'll add it here)
Have a nice time!
Edit: Well, Ihope I actually did find the right link: http://www.mathhelpforum.com/math-he...rial-latex.pdf