solving ordinary differential equations fig general oscillating system fig pendulum with forces this equation ishowevermore commonly reordered to mu ud ( because the differential equation is of second orderdue to the term we need two initial conditionsu ( ud kuand td we recover the note that with the choices original ode with = how can we solve ( )as for the simple ode we start by rewriting the second-order ode as system of two first-order odes / the initial conditions become and ( (