MathDB
Image of M by the rotation

Source: IMO Shortlist 1989, Problem 18, ILL 62

September 18, 2008
geometryalgebraconvex polygonareaIMO Shortlist

Problem Statement

Given a convex polygon A1A2An A_1A_2 \ldots A_n with area S S and a point M M in the same plane, determine the area of polygon M1M2Mn, M_1M_2 \ldots M_n, where Mi M_i is the image of M M under rotation RAiα R^{\alpha}_{A_i} around Ai A_i by \alpha_i, i \equal{} 1, 2, \ldots, n.