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Dissonance in E
Sep21-10, 07:28 AM
Hi I have a parametrisation of the unit circle
z = cos(t) + isin(t) = e^(it)
now i guess that the conjugate of that is the same but with a negative coefficient on the imaginary part, namely:
conj z = cos(t) - isin(t)
How does that extend to the e^(it) form? is the following true:
cos(t) - isin(t) = e^(-it)

Thanks

Office_Shredder
Sep21-10, 08:30 AM
e^{-it}=\cos(-t)+i\sin(-t). cosine is an even function, an sine is an odd function, so

e^{-it}=\cos(t)-i\sin(t)

Dissonance in E
Sep23-10, 09:43 AM
nice, thanks.