Determine if : R3 rightarrow R, given by f(x,y,z) = x2 - 3y2 + 2z2, is harmonic. Let f : R4 rightarrow R4 be given by f(x,y,z,w) = (xw, yz, xy, zw) and let g : R4 rightarrow R2 be given by g(x, y, z, w) = (wx2, wyz)). USE THE CHAIN RULE to compute D(g o f)(x,y,z, w). (NOTE: You must use the Chain Rule and show all your steps.)