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IMO Shortlist 2011, Algebra 3

Source: IMO Shortlist 2011, Algebra 3

July 11, 2012

functionalgebrafunctional equationIMO Shortlist

Problem Statement

Determine all pairs

(f,g)

of functions from the set of real numbers to itself that satisfy

g(f(x+y)) = f(x) + (2x + y)g(y)

for all real numbers

x

and

y

.
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