Perturbation Theory
Hmm if I&#x27;m understanding this correctly, (and recalling correctly,) there was a chapter at the end of Kleppner &amp; Kolenkow that dealt with this in the n=2 case: Basically assume the solution is a power series and truncate it past x^2. Well, you know how to solve diffeq&#x27;s like this, so do it and see the solutions. This was offered as a reason why so many things display periodic or seemingly periodic behavior. If the perturbations (x) are small enough to ignore the terms above x^3, then it&#x27;s just like the spring equations with dampening&#x2F;forcing.