QUESTION 2: a) Find the general solution of the equation dy dy dr + 4y = 4 - e- dr by using the method of undetermined coefficients. b) A vibrating spring with damping can be modelled by the differential equation d'y + b + ky = F(t), dy m dt? dt where m is the mass, b is the damping constant, k is the spring constant and F(t) is the force. A spring with spring constant 4 kg/s is attached to a lkg mass with damping constant 4 kg/s is forced periodically by a constant force of 2 cost kgm/s . Find the solution that satisfies y(0) = 1 and y (0) = 2.