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2014 BMO TST
4
4
Part of
2014 BMO TST
Problems
(1)
Albanian TST 2014 4th problem
Source:
4/22/2014
Find all functions
f
:
R
→
R
f:\mathbb{R}\to\mathbb{R}
f
:
R
→
R
such that
f
(
x
)
f
(
y
)
=
f
(
x
+
y
)
+
x
y
f(x)f(y)=f(x+y)+xy
f
(
x
)
f
(
y
)
=
f
(
x
+
y
)
+
x
y
for all
x
,
y
∈
R
x,y\in \mathbb{R}
x
,
y
∈
R
.
function
algebra solved
algebra
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