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CIIM
2009 CIIM
Problem 6
Problem 6
Part of
2009 CIIM
Problems
(1)
CIIM 2009 Problem 6
Source:
6/9/2016
Let
ϵ
\epsilon
ϵ
be an
n
n
n
-th root of the unity and suppose
z
=
p
(
ϵ
)
z=p(\epsilon)
z
=
p
(
ϵ
)
is a real number where
p
p
p
is some polinomial with integer coefficients. Prove there exists a polinomial
q
q
q
with integer coefficients such that
z
=
q
(
2
cos
(
2
π
/
n
)
)
z=q(2\cos(2\pi/n))
z
=
q
(
2
cos
(
2
π
/
n
))
.
CIIM 2009
CIIM
undergraduate