Ok, this one is really sticking me up:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]y'' - 2y' + 2y = e^{t}cos(t)[/tex]

I solved the homogenous version and got roots 1 +/- i and put these in to get the equation

[tex]y_h = c_1e^tcos(t) + c_1e^tsin(t)[/tex]

And I found that the root for e^tcos(t) should be (D- (1 +/- i)

But I'm completely stuck on what to do after this, the part that really confuses me is that in the answer, they only have a e^t sin(t) factor in the answer in addition to the normal homogenous answer, why does sin(t) appear without cos(t) ?

Thanks for your help,

~Lyuokdea

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# Problem with Complex Second Order Equations

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