IMO Shortlist 1998 problem G8
Avg:
Avg:
Let
be a triangle such that
and
. The tangent at
to the circumcircle
of triangle
meets the line
at
. Let
be the reflection of
in the line
, let
be the foot of the perpendicular from
to
, and let
be the midpoint of the segment
. Let the line
intersect the circle
again at
.
Prove that the line
is tangent to the circumcircle of triangle
.
commentEdited by Orl.



















Prove that the line


commentEdited by Orl.
Izvor: Međunarodna matematička olimpijada, shortlist 1998