This one got me alittle discombobulated. Initiallly I thought they wanted me to find a particular solution, which I did. But then later I saw it supplied to intial conditions. So I guessed y = Asin(5t)+Bcos(5t) then took derivatives, and applied the intial conditions but also was wrong. Here is the question: Find the solution of y'' + 5y' = 400sin(5 t) + 250cos(5 t) with y(0) = 8 and y'(0) = 8 . y = Here is my work: http://suprfile.com/src/1/1voo2y/lastscan.jpg [Broken] Thanks!