https://www.maplesoft.com/support/help/Maple/view.aspx?path=odeadvisor%2FDuffing
Duffing ODEs Description Examples Description The general form of the Duffing ODE is given by: Duffing_ode := diff(y(x),x,x)+y(x)+epsilon*y(x)^3 = 0; See...
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