y'' + 2y' + 5y = 0 (*)(adsbygoogle = window.adsbygoogle || []).push({});

OK, what I have done is computing the two roots y1 = exp(-x)*cos2x and y2 = exp(-x)*sin2x.

However, when I compute the derivatives of these two, and substitute into (*), the eq. doesn't equate 0.

Are my roots wrong?

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# Homework Help: Roots of a ODE

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