Approximate Solution for the Duffing-Harmonic Oscillator by the Enhanced Cubication Method
Figure 2
Relative errors for approximate frequency values obtained from Lim et al. [7], Beléndez et al. [12], Elías-Zúñiga et al. [21] solutions and by our derived cubication-equivalent nonlinearization solution given by (3.17) with the parameter value of .
