The surface S is described by R(u, v) = (2u, 3v, u + v$^2$), 0 ? u ? 2, 0 ? v ? 3.
scalar function f is defined by f(x, y, z) = xy + z.
Determine the surface differential $d\sigma$ in terms of u and v. Show your work.
Set up the basic surface integral in terms of u and v to calculate $\iint_S f \,d\sigma$.