solve the differential equation out completely using the method of undetermined coefficients. 

44. A mass-spring system is driven by the external force g(t) = 2 sin 3t + 10 cos 3t. The mass equals 1, the spring constant equals 5, and the damping coeffi- cient equals 2. If the mass is initially located at y(0) = -1, with initial velocity y'(0) = 5, find its equation of motion.