Has anyone tried to create a bode plot with mathcad for duffing oscillator?

[KemiaoJia]

Thanks a lot!

[Werner_E]

Sorry, no bode plot. Just a file saved from good old Mathsoft site. Post it for whatever it may be worth.

[AlanStevens]

Here's a possible approach. Can't vouch for its validity though - it's an example of my cavalier approach to topics I know nothing about!

Alan