Differentiate the fnction
Someone wants to give you an ulcer, don't they?
Simplify first:
I'm going to expand the numerator so my next step will be a bit clearer:
Now mulitply the numerator and denominator by x^4. We would normally need to be wary of doing this, but the domain of the original function excludes x = 0 anyway in this case.
You should be able to take the derivative now.
-Dan