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2002 Romania National Olympiad
2
There exists x_1,x_2 for an integrable function f
There exists x_1,x_2 for an integrable function f
Source:
December 8, 2010
function
integration
calculus
inequalities
real analysis
real analysis unsolved
Problem Statement
Let
f
:
[
0
,
1
]
→
R
f:[0,1]\rightarrow\mathbb{R}
f
:
[
0
,
1
]
→
R
be an integrable function such that:
0
<
∣
∫
0
1
f
(
x
)
d
x
∣
≤
1.
0<\left\vert \int_{0}^{1}f(x)\, \text{d}x\right\vert\le 1.
0
<
∫
0
1
f
(
x
)
d
x
≤
1.
Show that there exists
x
1
≠
x
2
,
x
1
,
x
2
∈
[
0
,
1
]
x_1\not= x_2, x_1,x_2\in [0,1]
x
1
=
x
2
,
x
1
,
x
2
∈
[
0
,
1
]
, such that:
∫
x
1
x
2
f
(
x
)
d
x
=
(
x
1
−
x
2
)
2002
\int_{x_1}^{x_2}f(x)\, \text{d}x=(x_1-x_2)^{2002}
∫
x
1
x
2
f
(
x
)
d
x
=
(
x
1
−
x
2
)
2002
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