pofteriore vero cafu 



^dydq^ ^dydq' ^dydp' 



In reliquis autem differentiationibus elementum 5 p fuppe- 

 ditat, praeter differentiationem folitam^ infuper membrum 

 d x( ^— ) , at vero elementum 3 q producit d x (^^ ) ; ele- 

 mentum porro dr producit ^x(|^), elementum ds vero 

 praebet d x {j^^) etc. quibus obferuatis obtinebuntur fe- 

 quentes aequationes: _ 



m. dx(p^) = b.{p^)-{-dx(^)-{-dx(i^), 



^dqdr^ ^dqdr' ^dpdr' ^dq^'' 



^dqds^ ^dqds' ^dpds^ ^dqdr' 



J. 25;. Ex his iam abunde perfpicitur, perpetuo^ quo 

 ties vel fola x, vel fola / variabilis accipitur, differentiatio- 

 nem more confueto inftitui debere, nihilque infuper effe ad- 

 iiciendum; fin autem reliquae litterae p, q, r, s, etc. va- 

 riabiles accipiantur , tum pro quolibet elemento fiue d p , 

 fiue d q, fiue d r, etc. praeterea vnum nouum terminum ac- 

 cedere debere. Hinc igitur pro folis elementis dx et dy 

 iam fequens theorema latiffime patens conftitui poteft: 



Theorema generale i. 

 Sl fuerit f Fdx=z Z^ tum femper erit 



^ ^\dx^dyy~\dx^dyy' 



Euo- 



