Wave functions like the one in Problem 40.34 can represent free particles moving with velocity v = p/m in the x-direction. Consider a beam of such particles incident on a potential-energy step U(x) = 0, for x < 0, and U(x) = U0 < E, for x > 0. The wave function for x < 0 is ψ (x) = Ae ik1x + be –ik1x, representing incident and reflected particles, and for x > 0 is ψ (x) = Ceik2x, representing transmitted particles. Use the conditions that both ψ and its first derivative must be continuous at x = 0 to find the constants B and C in terms of k1, k2 and A.