Have complimentary, can't get the particular

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Homework Statement



d4y/dx4 - a4y = eax

I have found the complimentary to be

Y(x)c = C1eax + C2e-ax + C3Cos(ax) + C4Sin(ax)

I can't seem to get get the particular. I've tried letting Y(x) = Aeax

Homework Equations





The Attempt at a Solution


 
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That gives me Aa^4exp(ax) - Aa^4exp(ax) = exp(ax) :(
 
Try Y=Ctexp(ax).

ehild

edit: "t" is a typo: It should be Y= Cxexp(ax)
 
Last edited:
ehild means xe^{ax}, not te^{ax}.
 
HallsofIvy said:
ehild means xe^{ax}, not te^{ax}.

Thank you, I edited it.

ehild
 
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