The use of complex math and imaginary numbers is routine in electronic analysis. This appendix includes some Web links, hints about complex number resources available on PCs, a note on Euler’s Formula and how it suggests the relationship between exponential functions and electronic sine waves, and a pretty good article summarizing the topic reprinted from Microsoft’s Encarta.
If you do a search for “imaginary numbers” on the Web you will get a great many hits. Some reasonable places to start are:
http://www.math.toronto.edu/mathnet/answers/imaginary.html (“Do Imaginary Numbers Really Exist?”)