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Problem 6
2012 function
2012 function
Source:
November 14, 2015
function
Problem Statement
Find all functions
f
:
R
⟹
R
f:R \implies R
f
:
R
⟹
R
, such for all
x
,
y
,
z
x,y,z
x
,
y
,
z
f
(
x
y
)
+
f
(
x
z
)
≥
f
(
x
)
f
(
y
z
)
+
1
f(xy)+f(xz)\geq f(x)f(yz) + 1
f
(
x
y
)
+
f
(
x
z
)
≥
f
(
x
)
f
(
yz
)
+
1
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