If I have a problem like(adsbygoogle = window.adsbygoogle || []).push({});

(N) sigma (K=0) Cos(Kpi)

can I just move the sigma sign inside the brackets? like

Cos(pi Sigma K)

just wondering because I have this on an assignment problem and we didn't learn it in class and the text book doesn't cover it either. If I can move it inside the answer is easy so I am just assuming thats how to do it.

Also, how do you guys write all the math symbols, etc. I see them in other posts but I am pretty much useless on a computer so I have no idea how to do it.

Thanks

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# Homework Help: Quick question on sums

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