MathDB
Two intersecting circles

Source: China TST 2006

June 18, 2006
geometryparallelogramgeometry unsolved

Problem Statement

Let the intersections of O1\odot O_1 and O2\odot O_2 be AA and BB. Point RR is on arc ABAB of O1\odot O_1 and TT is on arc ABAB on O2\odot O_2. ARAR and BRBR meet O2\odot O_2 at CC and DD; ATAT and BTBT meet O1\odot O_1 at QQ and PP. If PRPR and TDTD meet at EE and QRQR and TCTC meet at FF, then prove: AEBTBR=BFATARAE \cdot BT \cdot BR = BF \cdot AT \cdot AR.