Find f., fy, f-5,1, and f4,-4 for the following equation:
f(xy) = 2 + y^2
fx = (Type an exact answer, using radicals as needed.)
fy = L (Type an exact answer, using radicals as needed.)
fx-5,1 = (Type an exact answer, using radicals as needed.)
f4,-4 = (Type an exact answer, using radicals as needed.)