Thanks, yeah I've been trying to do it by parts for the last little while but it get's very messy, very quickly whenever I have to integrate by parts twice. I'm rubbish at calculus, I end up with the same solution but it's obviously even near being correct.
Homework Statement
Hi, I have to solve the following differential equation and while I can get the complimentary function I can't get the particular integral.
y'+30y=20sin(alpha*t)+alpha*cos(alpha*t)
Homework Equations
How do I integrate the product of e^30t and alpha*cos(alpha*t)...