MathDB
Problems
Contests
National and Regional Contests
PEN Problems
PEN H Problems
72
H 72
H 72
Source:
May 25, 2007
induction
number theory
relatively prime
absolute value
Diophantine Equations
Problem Statement
Find all pairs
(
x
,
y
)
(x, y)
(
x
,
y
)
of positive rational numbers such that
x
y
=
y
x
x^{y}=y^{x}
x
y
=
y
x
.
Back to Problems
View on AoPS