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1989 IMO Shortlist
10
10
Part of
1989 IMO Shortlist
Problems
(1)
Functional equation
Source: IMO Shortlist 1989, Problem 10, ILL 29
12/26/2005
Let
g
:
C
→
C
g: \mathbb{C} \rightarrow \mathbb{C}
g
:
C
→
C
,
ω
∈
C
\omega \in \mathbb{C}
ω
∈
C
,
a
∈
C
a \in \mathbb{C}
a
∈
C
, \omega^3 \equal{} 1, and
ω
≠
1
\omega \ne 1
ω
=
1
. Show that there is one and only one function
f
:
C
→
C
f: \mathbb{C} \rightarrow \mathbb{C}
f
:
C
→
C
such that f(z) \plus{} f(\omega z \plus{} a) \equal{} g(z),z\in \mathbb{C}
function
algebra
functional equation
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