Calculate the first-order partial derivative of the following:

for all (x,y) in $\displaystyle R^2$

I used this as a composition function and used the chain rule.

However, I am unsure of how to apply this formula.

First-order partial derivative of x would be

First-order pairtal derivative of y would be

My question is : how to compute this? Do I do another composition+chain rule?

Thank you.