Partial derivatives of a monomial Partial derivatives of a monomial Problem: Compute the partial derivatives of first and second order of the function f(x,y)=x3y5. Solution: We have fx=3x2y5, ∂y∂f=5x3y4, fxy=fyx=15x2y4, ∂x2∂2f=6xy5, fyy=20x3y3.