(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

the higher order equation y'' + y = 0 can be written as a first order system by introducing y' as another unknown besides y:

2. Relevant equations

d[y y']^{t}/dt = [y' y'']^{t}= [y' -y]^{t}

if this is du/dt = Au what is 2x2 matrix A?

3. The attempt at a solution

I think it's

[0 1]

[-1 0]

but then I get complex eigenvalues so I am a bit suspicious... could someone verify or help me out?

thanks.

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# Homework Help: Eigenvectors/values and diff equations

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