## yaro99 Group Title Steady state solution 4y''+12y'+9y=225-75sin(3t) I'm not sure what to do about the 225, I'd be able to solve it if it was just the sine term on the right. one year ago one year ago

1. TuringTest Group Title

Just add another constant in your guess for the particular if you are using undefined variables.

2. yaro99 Group Title

So it would be in the form $K+a*\cos(3t)+b*\sin(3t)$?

3. TuringTest Group Title

right

4. yaro99 Group Title

Cool, I got the solution. Thanks!

5. TuringTest Group Title

welcome :D