Euler-Savary's Formula for the Planar Curves in Two Dimensional Lightlike Cone

In this paper, we study the Euler-Savary's formula for the planar curves in the
lightlike cone. We first define the associated curve of a curve in the two dimensional lightlike cone Q2:Then we give the relation between the curvatures of a base curve, a rolling curve and a roulette which lie on two dimensional lightlike cone Q2.