Jessica and Matthew are running toward the point P along the straight paths that make a fixed angle of @ (Figure 1). Suppose that Matthew runs with velocity va (m/s) and Jessica with velocity 1 (m/s). Let f(x, y) be the distance from Matthew to Jessica when Matthew is a meters from P and Jessica is y meters from P. FIGURE 1 Show that f(x, y)=2+y2-2ry cos 0. . Assume that 0/3. Use the Chain Rule to determine the rate at which the distance between Matthew and Jessica is changing when =20, y = 12, v, 3 m/s, and = 2 m/s.