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SEEMOUS
2008 SEEMOUS
Problem 4
Problem 4
Part of
2008 SEEMOUS
Problems
(1)
integral inequality with integral condition, [0,1]->R
Source: SEEMOUS 2008 P4
6/17/2021
Let
n
n
n
be a positive integer and
f
:
[
0
,
1
]
→
R
f:[0,1]\to\mathbb R
f
:
[
0
,
1
]
→
R
be a continuous function such that
∫
0
1
x
k
f
(
x
)
d
x
=
1
\int^1_0x^kf(x)dx=1
∫
0
1
x
k
f
(
x
)
d
x
=
1
for every
k
∈
{
0
,
1
,
…
,
n
−
1
}
k\in\{0,1,\ldots,n-1\}
k
∈
{
0
,
1
,
…
,
n
−
1
}
. Prove that
∫
0
1
f
(
x
)
2
d
x
≥
n
2
.
\int^1_0f(x)^2dx\ge n^2.
∫
0
1
f
(
x
)
2
d
x
≥
n
2
.
calculus
integration
inequalities