IMC 2008 Day 2 P2 - Ellipses with common focus
Source: Problem 2
July 28, 2008
conicsellipsesearchgeometryratioanalytic geometrytrigonometry
Problem Statement
Two different ellipses are given. One focus of the first ellipse coincides with one focus of the second ellipse. Prove that the ellipses have at most two points in common.