Non-homogeneous 1st order diff equation

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SUMMARY

The discussion focuses on solving the non-homogeneous first-order differential equation y' + 30y = 20sin(αt) + αcos(αt). The user successfully identifies the complementary function as y = Ce^(-30t) but struggles to find the particular integral. The integration by parts method is suggested, specifically using u = e^(-30t) and dv = (20sin(αt) + αcos(αt)) dt, although the user finds this approach cumbersome and challenging due to the complexity of repeated integration.

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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) in order to find the particular integral?

The Attempt at a Solution



I've got y=Ce^(-30t) as the complimentary function but can get no further. Any help would be brilliant, thanks!
 
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Integrate by parts

u=e-30t

dv=20sin(αt)+αcos(αt) dt
 
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.
 

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