So far I got it down to ((4/3)n^3+(11/6)n^2)/((4/3)n^3)+(2n^2)+(2/3)n).

Would I be able to cancel out the ((4/3)n^3)s? So that it would be ((11/6)n^2)/((2n^2)+((2/3)n))?

Or can I simplify that even futher by combining the (n^2)s?