be a monic polynomial with integer coefficient. And suppose there exist 4 distinct integer 
such that 
.
such that 
such that ![\[f(2x+y) + f(x+f(2y)) = f(x)f(y) - xy\]](http://latex.artofproblemsolving.com/0/6/2/0623b7c328af6d088cfc5dd288afe3e17a94ff29.png)
for all reals 
and 
.
sastifying 
Y by
Consider five points on the plane so that each triangle with vertices in these three points has an area less than or equal to 
. Prove that the five points can be covered by a trapezoid of area at most 
.
. Prove that the five points can be covered by a trapezoid of area at most 
.
