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== cos(t-2) == | == cos(t-2) == | ||
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== Energy == | == Energy == | ||
Revision as of 05:13, 5 September 2008
cos(t-2)
Energy
u = (t-2)
$ E=\int_0^{2\pi}{|cos(u)|^2dt} $
$ E=\frac{1}{2}\int_0^{2\pi}(1+cos(2(u)))dt $
$ E=\frac{1}{2}((u+\frac{1}{2}sin(2(u)))|_{u=-2}^{u=2\pi-2} + C $
$ E=\frac{1}{2}(2\pi -2 + .0744 -(-2 - 0.0349)) +C $
$ E=\pi $
Power
$ E=\frac{1}{2\pi-0}\int_0^{2\pi}{|cos(u)|^2du} $
$ =\frac{1}{2\pi-0} *{\frac{1}{2}}\int_0^{2\pi}(1+cos(2u))du $
$ =\frac{1}{4\pi}((t-2)+\frac{1}{2}sin(2u))|_{u=-2}^{u=2\pi-2} $
$ =\frac{1}{4\pi}(2\pi+0-0-0) $
$ =\frac{1}{2} $
