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All-Russian Olympiad Regional Round
2007 All-Russian Olympiad Regional Round
11.2
11.2
Part of
2007 All-Russian Olympiad Regional Round
Problems
(1)
two quadratic polynomials
Source: Russian 2007
8/25/2007
Two quadratic polynomials
f
1
,
f
2
f_{1},f_{2}
f
1
,
f
2
satisfy f_{1}'(x)f_{2}'(x)\geq |f_{1}(x)|\plus{}|f_{2}(x)|\forall x\in\mathbb{R} . Prove that f_{1}\cdot f_{2}\equal{} g^{2} for some
g
∈
R
[
x
]
g\in\mathbb{R}[x]
g
∈
R
[
x
]
.
quadratics
algebra
polynomial
algebra proposed
Polynomials