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2018 IMO Shortlist
G3
G3
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2018 IMO Shortlist
Problems
(1)
Good triangles in a circle
Source: ISL 2018 G3
7/17/2019
A circle
ω
\omega
ω
with radius
1
1
1
is given. A collection
T
T
T
of triangles is called good, if the following conditions hold:[*] each triangle from
T
T
T
is inscribed in
ω
\omega
ω
; [*] no two triangles from
T
T
T
have a common interior point.Determine all positive real numbers
t
t
t
such that, for each positive integer
n
n
n
, there exists a good collection of
n
n
n
triangles, each of perimeter greater than
t
t
t
.
IMO Shortlist
geometry