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7
S 7
S 7
Source:
May 25, 2007
trigonometry
Miscellaneous Problems
Problem Statement
Let
n
n
n
be a positive integer. Show that
∑
k
=
1
n
tan
2
k
π
2
n
+
1
\sum^{n}_{k=1}\tan^{2}\frac{k \pi}{2n+1}
k
=
1
∑
n
tan
2
2
n
+
1
kπ
is an odd integer.
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