The One Dimensional Damped Forced Harmonic Oscillator Revisited
  In this paper we give a general solution to the problem of the damped harmonic oscillator under the influence of an arbitrary time-dependent external force. We employ simple methods accessible for beginners and useful for undergraduate students and professors in an introductory course of mechanics. 
G. Flores-Hidalgo and F.A. Barone
physics.class-ph physics.ed-ph