Consider a damped oscillator subject to a periodic triangle wave force F(t)
with period T, such that F(t+T) = F(t), F(t) = F_0(-1 + 4t/T) for 0 ≤ t ≤ T/2 and F(t) = F_0(3 - 4t/T) for T/2 ≤ t ≤ T. Assume the oscillator is underdamped. Compute the response of the oscillator forced by this F(t) using Fourier series.