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6
2014 Algebra #6
2014 Algebra #6
Source:
July 8, 2022
2014
Algebra Test
Problem Statement
Compute
cos
(
π
9
)
−
cos
(
2
π
9
)
+
cos
(
3
π
9
)
−
cos
(
4
π
9
)
\cos(\tfrac{\pi}{9})-\cos(\tfrac{2\pi}{9})+\cos(\tfrac{3\pi}{9})-\cos(\tfrac{4\pi}{9})
cos
(
9
π
)
−
cos
(
9
2
π
)
+
cos
(
9
3
π
)
−
cos
(
9
4
π
)
.
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