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:(adsbygoogle = window.adsbygoogle || []).push({});

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!

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# Y'' + 5y' = 400 sin(5 t) + 250 cos(5 t), but also has inital conditions? Diff EQ

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