I have seen the following identity used.(adsbygoogle = window.adsbygoogle || []).push({});

Exp[iw/2]-Exp[iw/2]=Exp[iw]-1

I can't find this in any book and I can't prove it myself.

The left side equals 2isin(w/2)

The right side equals cos(w)+isin(w)-1

On the face of it, that seems to make the identity absurd

How can one go about proving such an identity? Or is it wrong?

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# Identity for exponential function with imaginary arguments

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