An electric dipole consists of two equal but opposite electric charges, +q and -q, separated by a small distance d. If another charge Q is distance x from the center of the dipole, in the plane perpendicular to the line between +q and -q, and if x >> d, the dipole exerts an electric force F = KqQd/x³ on charge Q, where K is a constant. How much work does the electric force do if charge Q moves from distance x₁ to distance x₂?