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Unformatted text preview: 1 m = and 9 m = ? The corresponding frequencies differ by 2 , specifically, (9/8)2 (1/8)2 (8/8)2 ππ = + . 3. Explain in mathematical terms why the real part of the phasor signal is the same for and . 2 m = 6 m = A trigonometric identity gives cos[( ) ] ( 1) cos( ) n n n + = − , and for the two specified frequencies cos( ) n = for odd n . 4. What is the effect of changing the sign of the frequency, that is, changing the sign of the integer m ? The real part of the phasor is unchanged, while the sign of the imaginary part changes. In particular, note that the apparent “direction of rotation” does not necessarily change when the sign of the frequency changes – in contrast to the continuoustime case....
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 Spring '11
 whoknow

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