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Romanian Masters of Mathematics Collection
2011 Romanian Master of Mathematics
1
1
Part of
2011 Romanian Master of Mathematics
Problems
(1)
RMM2011, P 1, Day 1 - Find monotonous functions
Source:
2/25/2011
Prove that there exist two functions
f
,
g
:
R
→
R
f,g \colon \mathbb{R} \to \mathbb{R}
f
,
g
:
R
→
R
, such that
f
∘
g
f\circ g
f
∘
g
is strictly decreasing and
g
∘
f
g\circ f
g
∘
f
is strictly increasing.(Poland) Andrzej Komisarski and Marcin Kuczma
function
algebra proposed
algebra