Analytical Approximate Solutions for the Cubic-Quintic Duffing Oscillator in Terms of Elementary Functions

Figure 2

Comparison of approximate frequencies with exact frequencies for the cubic-quintic oscillator for (a) 𝜆₁=1, 𝜆₃=1, 𝜆₅=1 (red), (b) 𝜆₁=5, 𝜆₃=3, 𝜆₅=1 (green), and (c) 𝜆₁=1, 𝜆₃=10, 𝜆₅=1 (blue).