Matrix Inversion - complex admittance and impedance matrices (links to spreadsheets and Matlab stuff)
Exponential Integrals - Sine and Cosine integrals pop up in mutual impedance calculations
Euler's number (shows up in a variety of places)
Bessel functions - patterns of uniformly illuminated circular apertures (and FM modulation, too)
Wye/Delta (or T/Pi) transformations
Transmission line equations (including hyperbolic functions)
radio/math.htm - 11 July 2000 - Jim
Lux
(Radio Home Page) (Jim's Home
page)