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EGMO
2016 EGMO
1
1
Part of
2016 EGMO
Problems
(1)
Inequality with odd numbers.
Source: EGMO 2016 Day 1 Problem 1
4/12/2016
Let
n
n
n
be an odd positive integer, and let
x
1
,
x
2
,
⋯
,
x
n
x_1,x_2,\cdots ,x_n
x
1
,
x
2
,
⋯
,
x
n
be non-negative real numbers. Show that
min
i
=
1
,
…
,
n
(
x
i
2
+
x
i
+
1
2
)
≤
max
j
=
1
,
…
,
n
(
2
x
j
x
j
+
1
)
\min_{i=1,\ldots,n} (x_i^2+x_{i+1}^2) \leq \max_{j=1,\ldots,n} (2x_jx_{j+1})
i
=
1
,
…
,
n
min
(
x
i
2
+
x
i
+
1
2
)
≤
j
=
1
,
…
,
n
max
(
2
x
j
x
j
+
1
)
where
x
n
+
1
=
x
1
x_{n+1}=x_1
x
n
+
1
=
x
1
.
Inequality
algebra
inequalities
EGMO
n-variable inequality
Sequence