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Miklós Schweitzer
2017 Miklós Schweitzer
5
5
Part of
2017 Miklós Schweitzer
Problems
(1)
Places where |p(z)|=1
Source: Miklós Schweitzer 2017, problem 5
1/13/2018
For every non-constant polynomial
p
p
p
, let
H
p
=
{
z
∈
C
∣
∣
p
(
z
)
∣
=
1
}
H_p=\big\{z\in \mathbb{C} \, \big| \, |p(z)|=1\big\}
H
p
=
{
z
∈
C
∣
p
(
z
)
∣
=
1
}
. Prove that if
H
p
=
H
q
H_p=H_q
H
p
=
H
q
for some polynomials
p
,
q
p,q
p
,
q
, then there exists a polynomial
r
r
r
such that
p
=
r
m
p=r^m
p
=
r
m
and
q
=
ξ
⋅
r
n
q=\xi\cdot r^n
q
=
ξ
⋅
r
n
for some positive integers
m
,
n
m,n
m
,
n
and constant
∣
ξ
∣
=
1
|\xi|=1
∣
ξ
∣
=
1
.
algebra
polynomial