Partial Derivative of Exponential Quotient

Question

How would I go about finding the partial derivative with respect to $y$ of $z = (x^2/(1-y^3))^{0.5}$

The way I thought to do it was to get rid off the brackets and square root, making $x/(1-y^{1.5})$. However, I have the answer for this problem (given by a book), and it does not match the answer given by doing it this way.

Thanks in advance for any help.

EDIT: I should add that the answer of the partial with respect to X did match the method I used to solve this problem.

Answer 1

$$z=\sqrt{\frac{x^2}{(1-y^3)}}=|x|(1-y^3)^{-0.5}$$ $$\frac{\partial z}{\partial y}=|x|(-.5)(1-y^3)^{-1.5}(-3y^2)=\frac{1.5y^2|x|}{\sqrt{(1-y^3)^3}}=1.5y^2\sqrt{\frac{x^2}{(1-y^3)^3}}$$

Answer 2

Substitute $u = 1 - y^3$ and use the chain rule.