2009 UNCO Math Contest II Problems/Problem 6
Revision as of 21:14, 19 October 2014 by Timneh (talk | contribs) (moved 2009 UNC Math Contest II Problems/Problem 6 to 2009 UNCO Math Contest II Problems/Problem 6: disambiguation of University of Northern Colorado with University of North Carolina)
Problem
Let each of distinct points on the positive
-axis be joined to each of
distinct points on
the positive
-axis. Assume no three segments
are concurrent (except at the axes). Obtain
with proof a formula for the number of interior
intersection points. The diagram shows that
the answer is
when
and