For unlimited access to Homework Help, a Homework+ subscription is required.
Partial Derivatives
Let z = f(x,y) and x = r cos theta and y = r cos theta
Show that (del^2 z / delx^2) + (del^2 z / dely^2) = (del^2 z / delr^2) + (1/r^2)*(del^2 z / del theta^2) + [(1/r)*(del z / del r)]