In one of my electronics textbooks I have the following equation related to feedback in amplifiers:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]K_f = \frac{K}{1-K\beta}[/tex]

[tex]\frac{dK_f}{K_f} = \frac{1}{1-K\beta}\frac{dK}{K}[/tex]

I'm not sure how this was derived - how was Kf differentiated with respect to itself?

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# Differentiation of a function with respect to itself

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