Find a solution to the following D.E.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\frac{dy}{dx} + \frac{x}{y}=0[/tex]

[tex]\frac{dy}{dx}=-\frac{x}{y}[/tex]

Separate variables...

[tex]ydy = -xdx[/tex]

Integrate both sides...

[tex]\frac{y^2}{2}=-\frac{x^2}{2}[/tex]

Multiply both sides by 2, and here is where my problem arises...

[tex]y^2=-x^2[/tex]

Stuck. [itex]x^2[/itex] will always be positive, so after applying the negative, I can't take the squareroot. It has to be a simple mistake. Please give a small bit of help or a small hint.

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# Homework Help: Very simple D.E.

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