How do I find a closed expression for $$\sum_{k=1}^n\cos(kA)$$ any idea about how to go about doing this?
Thanks in advance
2026-04-22 07:09:37.1776841777
A closed expression for $\sum_{k=1}^n\cos(kA)$
39 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in TRIGONOMETRY
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