MathDB
<PAC=2<CPA

Source: French TST 2005 pb 5.

May 27, 2005
trigonometrygeometry solvedgeometry

Problem Statement

Let ABCABC be a triangle such that BC=AC+12ABBC=AC+\frac{1}{2}AB. Let PP be a point of ABAB such that AP=3PBAP=3PB. Show that PAC^=2CPA^.\widehat{PAC} = 2 \widehat{CPA}.