Nunc quacratur angulns p vt Ct 



^ ^ ^ ' = taiig. (3 et 



£ fc' (2 a—c^ — c) fiii. le' — J (f' — <•)' cof. e 



^ 2ff'(2fl — f — r') fin. Je' — fl (t"' -<?)' 



a c c' '^z a — c — c') i\n.\z' — a (<;' — fj' col". e 

 critquc 



tan^. (3 fin. 5 4- cof. 5 — M, hincque 

 cof. (5 - p) — M cof p , 



liinc quum dctur M cof (3, cognofcctur cof. (5— (3), ex 

 quo ob cognitum angulum |3, dabitur augulus 5. 



§. 17. Quum in fupcrioribus fit 



a f t-'(c -\-c'-za) (i- cof (p cof CP') - i<r' (f'-<7) fin. (^* 

 -zc" [c — a) fin. 4)" zz o , ob 



2 fin. (J)' — I - cof 2 4) i 2 fin. (p" — I - cof 2 c|)', 

 fiet 



a <: f* (r -}- <r' - 2 fl) (r - cof. tp cof Cp') 



- f * (c' - fl) ( I - cof 2 (p) - 2 1' = (<; - fl) (i - cof 2 Cj)')) 

 tumquc quum fit Cj)' — ^ — Cj), crit 



cof Cj)' — cof c cof CP 4- fin. e fin. Cj) ct 

 cof 2 (^' — cof 2 c cof 2 Cj) 4- fin. 2 e fin. 2 Cj) , 

 hinc prodibit ii\a acquatio: 



o— 2cc' {c ■]-('- 2 fl) (i -cof Ecof C|i'-fin.Efin.Cpcof Cj)) 

 -f^^f^-fl^^i-cof^Cp^-f^^^f-flXi-cofaecofaCp-fin.iefin.^^)), 

 tum \tio ob 



2 cof. 



