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ChildishHambino
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\displaystyle\frac{1}{1-e^{j\theta}}=\frac{1}{2}(1+jcot(  \frac{\theta}{2})
Need help on this question, i've tried to rationalize after converting to mod arg form and I got;
\displaystyle\frac{1-cos(\theta)+jsin(\theta)}{2(1-cos(\theta)}
But I'm pretty sure I'm not going the right way about it because of the half theta on the RHS. Which leads me to thinking it's something to do with the identity \alpha + 1=2cos(\frac{\theta}{2})e^j\frac  {\theta}{2}}
and the other one. but how do I get it in that form?

Thanks in advance.
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brianeverit
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(Original post by ChildishHambino)
\displaystyle\frac{1}{1-e^{j\theta}}=\frac{1}{2}(1+jcot(  \frac{\theta}{2})
Need help on this question, i've tried to rationalize after converting to mod arg form and I got;
\displaystyle\frac{1-cos(\theta)+jsin(\theta)}{2(1-cos(\theta)}
But I'm pretty sure I'm not going the right way about it because of the half theta on the RHS. Which leads me to thinking it's something to do with the identity \alpha + 1=2cos(\frac{\theta}{2})e^j\frac  {\theta}{2}}
and the other one. but how do I get it in that form?

Thanks in advance.
Use the double angle identities to change all thetas into half thetas.
Use \cos\theta=1-2\sin^2 \frac{\theta}{2} to deal; with \cos\theta
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