2)capm #" =rM  4  ӗ(     p1H   XahLee.org, 2004.   0 @   1JĠ ӗ(   DJĀHHE=J0JC.Ct  JÐ ӗ(   CJpHHEM4J0JCqC ).J€ ӗ(   BJ`HHEMXJ°0JCCZ m ӗ(   AJՀ08<JJpJՀ/JpJpJCdC  Nf ӗ(     8P[Definition: Harmonic Conjugacy. Four concurrent lines a,b,c,d, are said to form a harmonic set if there is a quadrilateral of which two opoosite vertices lies on a and two other opposite vertices on b, while the remaining vertices lie on c and d. We say that c and d are harmonic conjugates (of each other) with respect to a and b, and we write H(ab,cd) as an abbreviated statement of this relation. To construct d, given a,b,c, we draw any trinagle pqr whose vertexes q*r, r*p, p*q, lie on a,b,c, respectively. This determines a quadrilateral pqrs, where s = (a*p)(b*q). We thus obtain d = (r*s)(a*b).  l' ӗ(   p}0(Gt}Pt&t&Gt~D,./ /CqCC.Ct? 'FP ӗ(   r}0(Gt}Pt&t&Gt~D,./ /CCZCqC?;;  ;' ӗ(   q}0(t~t}Pt&t&Gt~Ds0t~PC.CtCCZ?ڤΎ&t'# ӗ(   a}0(Gt}Pt&t&Gt~D,./ /CCZCdC ?' ӗ(   b}0(Gt}Pt&t&Gt~D,./ /CqCCdC ?'x ӗ(   c}0(Gt}Pt&t&Gt~D,./ /C.CtCdC ?܍܎/x4}J ӗ(   FJ̠HHELJ0JCCw  J@ ӗ(   EJ HHEM@Jp0JCmCf ' ӗ(   s YPn4BD3J0JJJJCCwCmCf?  E_ ӗ(   GE_HHEME` 0ECaCu'v '^ ӗ(   t Q0(