MathDB
Family of segments

Source: 2024 AIME II P12

February 8, 2024
AIMEAIME IAIME II

Problem Statement

Let O(0,0)O(0,0), A(12,0)A(\tfrac{1}{2},0), and B(0,32)B(0, \tfrac{\sqrt{3}}{2}) be points in the coordinate plane. Let F\mathcal{F} be the family of segments PQ\overline{PQ} of unit length lying in the first quadrant with PP on the xx-axis and QQ on the yy-axis. There is a unique point CC on AB\overline{AB}, distinct from AA and BB, that does not belong to any segment from F\mathcal{F} other than AB\overline{AB}. Then OC2=pqOC^2 = \tfrac{p}{q} where pp and qq are relatively prime positive integers. Find p+qp + q.