Re: Multiple angle help!!

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Article #92

#92

From: John Fitch
Date: Fri, 06 Sep 1996 00:00

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Remember that exp(ix) = cos(x) + i sin(x)

so exp(ix)^n = exp(inx)

   (cos(x) + i sin(x))^n = cos(nx) + i sin(nx)

Considering real and imaginary parts

cos(nx) = REAL((cos(x)+i sin(x))^n)

sin(nx) = IMAG((cos(x)+i sin(x))^n)

and remember the binomial theorem.......

Rest left as an exercise!

==John ff

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From: John Fitch <jpff@maths.bath.ac.uk>
Subject: Re: Multiple angle help!!
Date: 1996/09/06
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