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Product and cos
Geometry
Level 3
\[\large \displaystyle\prod \limits^{14}_{k=1}\cos \left( \frac{k \pi }{15} \right) =\ ? \]
Image Credit:
Wikimedia László Németh
.
\[\frac {2}{3}\]
\[\frac {1}{2}\]
\[\bigg(\frac {1}{2}\bigg)^{14} \]
0
14
\[ -\bigg(\frac {1}{2}\bigg)^{14} \]
1
Submit
Excel in math and science
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