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| − | <math>=-\frac{1}{4}e^{j3\pi n}-\frac{1}{4}e^{-j3\pi n}+\frac{1}{j2}e^{3\pi n}-\frac{1}{j2}e^{-j3\pi n}</math> | + | <math> =-\frac{1}{4}e^{j3\pi n}-\frac{1}{4}e^{-j3\pi n}+\frac{1}{j2}e^{3\pi n}-\frac{1}{j2}e^{-j3\pi n}</math> |
Revision as of 15:32, 26 September 2008
$ x[n]=-\frac{1}{2}cos(3\pi n)+sin(3\pi n)\! $.
$ x[n]=-\frac{1}{2}[\frac{e^{j3\pi n}+e^{-j3\pi n}}{2}]+\frac{e^{j3\pi n}-e^{-3\pi n}}{j2} $
$ =-\frac{1}{4}e^{j3\pi n}-\frac{1}{4}e^{-j3\pi n}+\frac{1}{j2}e^{3\pi n}-\frac{1}{j2}e^{-j3\pi n} $
