Question 298073
dz/dx = 2xy
z=x^2y+C



dz/dy = x^2 
z=x^2y+C


z = f(x,y) = x^2y+C



z=x^2y+C

z=(r*cos(theta))^2*r*sin(theta)+C


z=r^2*cos^2(theta)*r*sin(theta)+C


z=r^3*cos^2(theta)*sin(theta)+C


dz/d(theta) = r^3[-2cos(theta)sin^2(theta)+cos^3(theta)]