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PEN H Problems
72
72
Part of
PEN H Problems
Problems
(1)
H 72
Source:
5/25/2007
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
.
induction
number theory
relatively prime
absolute value
Diophantine Equations