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Math Prize For Girls Problems
2017 Math Prize for Girls Problems
20
20
Part of
2017 Math Prize for Girls Problems
Problems
(1)
Math Prize 2017 Problem 20
Source:
9/27/2017
Compute the value of the sum
∑
k
=
1
11
sin
(
2
k
+
4
π
/
89
)
sin
(
2
k
π
/
89
)
.
\sum_{k = 1}^{11} \frac{\sin(2^{k + 4} \pi / 89)}{\sin(2^k \pi / 89)} \, .
k
=
1
∑
11
sin
(
2
k
π
/89
)
sin
(
2
k
+
4
π
/89
)
.
Math Prize for Girls