Hi all, I'm trying to solve the following expression for w when w is entirely real (no imaginary component). It is part of a circuits problem where I have to design a band pass filter. Note that I'm using j instead of i to denote the imaginary component.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\frac{jwLR+\frac{L}{C}+\frac{R}{jwC}}{R+\frac{1}{jwC}}[/tex]

To be clear, I'm only looking for a relationship between R, L, and C which would cause the above expression to be entirely real. This is basically the solution for the resonant frequency of my circuit. So w at resonance equals some relationship of R, L, and C. I really appreciate any help with this.

For anyone who is interested, this is my result for the transfer function (Vout/Vin) of an RLC combination I'm trying. The RLC configuration is L in series with R and C in parallel. In my case, the pure series RLC bandpass filter will not work as it yields an output voltage below what is required and I cannot use active components.

Thanks,

mrb427

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# Homework Help: Finding the Real Points of a Complex Function

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