I`ve been able to use excel to plot the trajectory of a harmonically driven duffing oscillator for arbitrary parameters using Runge-Kutta method. I would like to do the same thing for the frequency response, but I simply can not figure out how. I am not very mathematically advanced so the first thing I did was look for a formula. I found things such as those in the attached images, where A is the amplitude which I would like to plot as a function of w (frequency) (and all other terms are knowns). But I have no idea how to make use of these equations. I dont know how to isolate the amplitude and don`t know how to graph it without isolating A.(adsbygoogle = window.adsbygoogle || []).push({});

Can someone explain to me how one would plot the frequency response to a duffing oscillator ? It must be obvious, as every book I`ve read skips right over it as if it deserves no explicit explanation, but I am at a loss and have been trying for a while. Sorry if this is a dumb issue, I have no background in this area

Edit: I`ve also attached the VBA code I`m using in case that provides some insight somehow

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# How to graph the duffing frequency response

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