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

Rewrite the 2nd oder non linear D.E [itex]\frac{d^2x}{dt^2}+x^2+x=0[/itex]

as a series of 1st order equations

2. Relevant equations

[itex]a\frac{d^2x}{dt^2}+b\frac{dx}{dt}+cx=0[/itex]

[itex]\frac{dx}{dt}=y[/itex]

[itex]\frac{dy}{dt}=-\frac{c}{a}x-\frac{b}{a}y[/itex]

3. The attempt at a solution

a=1, b=0 , c=1

SO

[itex]\frac{dx}{dt}=y[/itex]

[itex]\frac{dy}{dt}=-\frac{1}{1}x-\frac{0}{1}y[/itex] = [itex]-x[/itex]

Is that right?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Rewrite the 2nd oder non linear D.E as a series of 1st order equations

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