This is a basic simplification, but I'm going to post this here because it becomes homogeneous, and I know [tex]v = \frac{y}{x}[/tex] but I don't see this simplification, I don't understand how it gets from this...(adsbygoogle = window.adsbygoogle || []).push({});

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

To THIS:

[tex] = \frac{v-1}{v+1}[/tex] (I'm just only showing the RHS here)

If someone wouldn't mind explaining it, that would be great because I'm lost, unless this is a special rule.

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# Homogeneous DE simplification

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