MathDB
Binary operation *star*

Source:

August 29, 2010
vectorgeometrygeometric transformationrotationcomplex numbersgeometry unsolved

Problem Statement

We define a binary operation \star in the plane as follows: Given two points AA and BB in the plane, C=ABC = A \star B is the third vertex of the equilateral triangle ABC oriented positively. What is the relative position of three points I,M,OI, M, O in the plane if I(MO)=(OI)MI \star (M \star O) = (O \star I)\star M holds?