IMO Shortlist 1973 problem 2
Dodao/la:
arhiva2. travnja 2012. Given a circle
, find the locus of vertices
of parallelograms
with diagonals
, such that
is inside
.
%V0
Given a circle $K$, find the locus of vertices $A$ of parallelograms $ABCD$ with diagonals $AC \leq BD$, such that $BD$ is inside $K$.
Izvor: Međunarodna matematička olimpijada, shortlist 1973