— 100 — 



x/ x/.cosB x./'S x/'.cosB 



r r' = BW - Br = ^ + -L^-5 Ag' ^-.-.5 



sinB sinB sinBj sinB 



X.J — X3" + (x/ — x/')cosB 



= r-^ = ist 



SinB 



, fx ' — X '' + (x/ - x/')cosBT^ 



^ ^ ~l sinB J "^ ^"^1 ""i ^ 



=[^(x3'-X3"f+(x/-x/'f+2(x3'-X3")(x/~x/')cosB]:sin^B 



daaberx^' .sinA-f-Xg' . sinB-j-X3' . sinC = d .sinA. sinB . sinC u. 

 x^". sin A-j-Xg". sinB + X3".sinC = d, sinA.sinB. sinCist, 

 also (x/ — x/') sinA + (X2' — Xg") sinB -j- (Xg' — Xg'^jsinC = 0, 

 so folgt durch quadrieren: 2(Xg' — X3")(x^' — x^") 



(x/ — x^")' sin'B - (x/ - x/')'sin'A — (Xg' — x^"f. sin^C 



sin A . sin C 



also FP^^= sinC(x3' — x^"f(smA — cosBsinC) 



-}- sinA(x/ — x/'nsinC — cosBsinA) 



-\- sin^BcosB(x2' — Xg")" [ : sinA . sin^B . sinC 



= I sinA(x/ — x/ ')^ cos A. sinB -j- sinB(x2' — Xg"/ cos B . sinB 



+ sinC(x3' — X3")^ cos C. sinB | : sinA. sin^B . sin C 



= { (x/— x/'fsin2A + (x.; — X2"fsin2B + (x3' — X3"fsin2c| 



: 2sinA. sinB.sinC w. z. b. w. 



