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CIIM
2014 CIIM
Problem 1
CIIM 2014 Problem 1
CIIM 2014 Problem 1
Source:
August 9, 2016
CIIM
CIIM 2014
undergraduate
function
Problem Statement
Let
g
:
[
2013
,
2014
]
→
R
g:[2013,2014]\to\mathbb{R}
g
:
[
2013
,
2014
]
→
R
a function that satisfy the following two conditions:i)
g
(
2013
)
=
g
(
2014
)
=
0
,
g(2013)=g(2014) = 0,
g
(
2013
)
=
g
(
2014
)
=
0
,
ii) for any
a
,
b
∈
[
2013
,
2014
]
a,b \in [2013,2014]
a
,
b
∈
[
2013
,
2014
]
it hold that
g
(
a
+
b
2
)
≤
g
(
a
)
+
g
(
b
)
.
g\left(\frac{a+b}{2}\right) \leq g(a) + g(b).
g
(
2
a
+
b
)
≤
g
(
a
)
+
g
(
b
)
.
Prove that
g
g
g
has zeros in any open subinterval
(
c
,
d
)
⊂
[
2013
,
2014
]
.
(c,d) \subset[2013,2014].
(
c
,
d
)
⊂
[
2013
,
2014
]
.
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