you may want to consider writing as 3 expressions
1-3/x +1/x^3 and using the power rule on each
otherwise all you need is the quotient rule
Work from the outside in! That is, the main function is a quotient, so apply the quotient rule to it:
Then differentiate numerator and denominator. While " " and " " are "products", you don't really use the "product rule": use the "power law", and the fact that, for c a constant, .