MEMO 2016 ekipno problem 5
Kvaliteta:
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Avg: 6.0Let be an acute-angled triangle with
, and let
be its circumcentre. The line
intersects the circumcircle
of
a second time in point
, and the line
in point
. The circumcircle of
intersects the line
a second time in point
. The line
intersects the line
in point
. The line through
parallel to
intersects the altitude of the triangle
that passes through
in point
.
Prove that .
Source: Srednjoeuropska matematička olimpijada 2016, ekipno natjecanje, problem 5