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International Contests
IMO Shortlist
1983 IMO Shortlist
17
17
Part of
1983 IMO Shortlist
Problems
(1)
Distance of points
Source:
9/9/2010
Let
P
1
,
P
2
,
…
,
P
n
P_1, P_2, \dots , P_n
P
1
,
P
2
,
…
,
P
n
be distinct points of the plane,
n
≥
2
n \geq 2
n
≥
2
. Prove that
max
1
≤
i
<
j
≤
n
P
i
P
j
>
3
2
(
n
−
1
)
min
1
≤
i
<
j
≤
n
P
i
P
j
\max_{1\leq i<j\leq n} P_iP_j > \frac{\sqrt 3}{2}(\sqrt n -1) \min_{1\leq i<j\leq n} P_iP_j
1
≤
i
<
j
≤
n
max
P
i
P
j
>
2
3
(
n
−
1
)
1
≤
i
<
j
≤
n
min
P
i
P
j
geometry
geometric inequality
optimization
minimization
maximization
IMO Shortlist
point set