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Iran MO (3rd Round)
2020 Iran MO (3rd Round)
1
25% disscount
25% disscount
Source: Iranian Third Round 2020 Algebra exam Problem1
November 20, 2020
Problem Statement
find all functions from the reals to themselves. such that for every real
x
,
y
x,y
x
,
y
.
f
(
y
−
f
(
x
)
)
=
f
(
x
)
−
2
x
+
f
(
f
(
y
)
)
f(y-f(x))=f(x)-2x+f(f(y))
f
(
y
−
f
(
x
))
=
f
(
x
)
−
2
x
+
f
(
f
(
y
))
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