Hello, another dull question on binomial expansion (approximation). I cannot follow the derivation for the approximate values of the two constants [tex]\alpha[/tex] and [tex]\beta[/tex].(adsbygoogle = window.adsbygoogle || []).push({});

(Text on propagation coefficient of TEM waves in transmission lines - constants of attenuation and phase-shift)

Given

[tex]\gamma = \alpha + j\beta = \sqrt{(R + j\omega L)(G + j\omega C)}[/tex]

Through "binomial expansion", taking the expansion to the third term.

[tex]\alpha \approx \frac{1}{2} (R\sqrt{\frac{C}{L}} + G\sqrt{\frac{L}{C}})[/tex]

[tex]\beta \approx \omega\sqrt{LC}(1 + \frac{1}{8\omega^2}(\frac{R}{L} - \frac{G}{C})^2)[/tex]

I know this is a messy one, so just a clue on what this is about would be great =D

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# Binomial Help Again

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