•>|4I ) xo ( ^<. 



Tbi ciim fit PP — QQ fundjo par ipfius s, valor pro 

 jr fponte euadet fua(flio impar. Obtinebitur igitur; 

 x=/PP R</5r-/QQR</2 et 



j'ir/PPR^3-2/PQR</s+-/QQR^2. 

 Facillime autem nunc pro P, Q, R eiusmodi funftione? 

 alfignare licebit, vt fingulae hae formulae fiant integrabi- 

 les. Veluti fi earum loco poteftates ipfius z accipiantur, 

 \el etiam formulac rationales integrae quaccunque. 



De parabola cubicali (ecunda 



^ .*.*■•• /^ . n. 



tanqiiam fimpUcifnma curua Problemati 

 fatisfaciente. 



§. II. Simpliciflimus cafus hinc deducetur fi fu- 

 matur ?:zia et Q^-s, vnde fit 



xzzifaaKd z—/z zRd z ct 

 yz^faaKdz-{-2fazKdz~{-/zzRdz. 

 Nunc porro fumamus K — t\, et integrando prodibit 



bbx — aaz — lz^ et bby — a az ~\- azz -i-'^ z\ 



Vbi tantum opus eft quantiratem z ehminare, vt aequatio 

 inier coordinatas x et y obtineatur, id quod per lcqucn- 

 tcb operatioues commodiflime expedietur. 



§. 12. Addantur duae aequationes inuentae , Tt 

 prodeat haec: 



bb{x-{-y^^2aaz~]-azZj vndc fit 



z z -^ 2 a z -^^-^ ix -i- y^ y 



ideoquc 



