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Putnam
2022 Putnam
B6
B6
Part of
2022 Putnam
Problems
(1)
2022 Putnam B6
Source:
12/4/2022
Find all continuous functions
f
:
R
+
ā
R
+
f:\mathbb{R}^+\rightarrow \mathbb{R}^+
f
:
R
+
ā
R
+
such that
f
(
x
f
(
y
)
)
+
f
(
y
f
(
x
)
)
=
1
+
f
(
x
+
y
)
f(xf(y))+f(yf(x))=1+f(x+y)
f
(
x
f
(
y
))
+
f
(
y
f
(
x
))
=
1
+
f
(
x
+
y
)
for all
x
,
y
>
0.
x, y>0.
x
,
y
>
0.
Putnam
Putnam 2022