Identity for exponential function with imaginary arguments

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ParityCheck
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I have seen the following identity used.
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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ParityCheck said:
Exp[iw/2]-Exp[iw/2]=Exp[iw]-1

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

Hi ParityCheck ! Welcome to PF! :smile:

(eiw/2 - e-iw/2)eiw/2 = eiw - 1 :wink:
 
Thanks. I was making it way too complicated with trig identities and series and...