Given the following function, find f_(xx), f_(xy), f_(yyx) [Note: f_(xx), for instance, is f subscript xx].

f(x,y) = e^(4x) - sin(y^2) - sqrt(xy)

Answers in book:

f_(xx) = 16e^(4x) + (1/4)*sqrt(y/(x^3))

f_(xy) = -1/(4*sqrt(xy))

f_(yyx) = 1/(8*sqrt(x^3*y^3))