MathDB
Nordic MC 2007 Q4

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March 3, 2013
ratiogeometrygeometry unsolved

Problem Statement

A line through AA intersects a circle at points B,CB,C with BB between A,CA,C. The two tangents from AA intersect the circle at S,TS,T. STST and ACAC intersect at PP. Show that APPC=2ABBC\frac{AP}{PC}=2\frac{AB}{BC}.