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Vojtěch Jarník IMC
2008 VJIMC
Problem 1
Problem 1
Part of
2008 VJIMC
Problems
(2)
FE over Z, 19f(x)-17f(f(x))=2x
Source: VJIMC 2008 2.1
6/17/2021
Find all functions
f
:
Z
→
Z
f:\mathbb Z\to\mathbb Z
f
:
Z
→
Z
such that
19
f
(
x
)
−
17
f
(
f
(
x
)
)
=
2
x
19f(x)-17f(f(x))=2x
19
f
(
x
)
−
17
f
(
f
(
x
))
=
2
x
for all
x
∈
Z
x\in\mathbb Z
x
∈
Z
.
fe
functional equation
algebra
complex roots of polynomial
Source: VJIMC 2008 1.1
6/16/2021
Find all complex roots (with multiplicities) of the polynomial
p
(
x
)
=
∑
n
=
1
2008
(
1004
−
∣
1004
−
n
∣
)
x
n
.
p(x)=\sum_{n=1}^{2008}(1004-|1004-n|)x^n.
p
(
x
)
=
n
=
1
∑
2008
(
1004
−
∣1004
−
n
∣
)
x
n
.
complex numbers
Polynomials
algebra
polynomial