I know how to solve the following ODE with variation of parameters:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]y''+4y=4\sec{\left(2t\right)}.[/tex]

Is there any way to solve this with undetermined coefficients? So far I have tried Y_{p}=Acos(2t)+Bsin(2t), but that didn't work.

Thanks for the help.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Undetermined Coefficients / Variation of Parameters

**Physics Forums | Science Articles, Homework Help, Discussion**