-+- (A -hV>)b (fin. q. dd. cof. q — cof. ^. </</. fin. /7)^ _ 

 -H A fl ( fin. q. d d.co^.p — cof. ^. </ d. fin. p ) ^ "" 

 Ad has aeqiiationcs rcfoliicndas notemus eflTe: 



cof. p. d d. fin. p — fin. p. d d. cof. p ^d dp 



coi. p. d d. f\n.q — fin. p.d d. cof. q - d d q cof. (q—p) 



— d q' fin. (^ — />) 



fln. ^. </ d. cof. /7 — cof q, d d. fm. q — — ddq 



fin. <7 fl' </. cof.p — cof. ^. ^</. Cin. p zn — d d p coC. ^q — py 



— d p- fin. (^ — p). 



Hi ergo valorcs in lupcrioribiis aequationibus fubftituti 

 pracbi-nt illas : 



(R-i C) a ddp^-C b(ddq col. (q-p) -dq' fin. (q-p)) = o 

 et 



- (A+B) b d d q-A a(d dp co(.(q-p)+d p' Cm (q-p))-o. 

 Ponamus 



(B -4- C) a — . ( A ->- B) fc — „ 



\t habcamus h.is duas acquationcs: 



1 °. m d d p ~{- d d q cof (q~ p) — d q' fin. (q — />) - o 

 2". ?i d d q -\- d d p cof. (^ -/)) + ^p' fin. (^-/)) - o 



cx quibus ambos angulos incognitos p ct /y cliccrc opor- 



tct , id quod fcqucnii modo liicccdct. 



Intcf^rcntur hac duac acqiuitioncs, quod ficri licct 

 morc folito, ac rcpcrictur: 



;;/ d p -i d q cof (q — p) —fdp d q fin. (q - p) ~ conO. 

 :i d q -}- d p cof. (q — p) + j d p d q Ur\. (q - p) ::. conlh 



vndc patct, fuir.mam harum fornuilarum a formulis intc- 

 gralibus ioic libcram, ita vt h'nc adipifcamur h.inc :ic- 



(jua- 



