This is a question thats stumping both myself, and my friends who are on maths degrees!(adsbygoogle = window.adsbygoogle || []).push({});

So...

cos(x) can be written as [tex]\frac{1}{2}(e^{ix}+e^{-ix})[/tex] correct?

so does that make its conjugate [tex]\frac{1}{2}(e^{-ix}+e^{ix})[/tex], i.e. cos(x) again? or does the switching of the sign go in front of the e? Its been a long time since I used complex numbers, so I (and my friends) are a little rusty! Any help would be appreciated.

Thanks

Brewer

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# I'm having (another) thick moment (complex numbers)

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