:i<?S ADDITJMENTFM JD DISSERTAT, 



§. 28. His praemiflis fi fiierit P talis fiinAio ip- 

 'fius X et a^ Yt BP comprehentliitur in hac forma^f 

 (X-H-A) leu piiirium huiusmodi formularum aggrega- 

 to, femper dari poterit aequatio modukris differentia- 

 Us primi gradus. Namqiic eric ?£lAdx — Z'\--\-Q^ 

 ciadK feu B?dAdx:=.z dBdX-hBQ/IadX. Qine 

 aequado ob datum Q_ efl: modularis relpoudeus acqua- 

 tioni propofitae. 



§, 29. Dcinde fi P talis fit fiinctio ipfirum a ct x 

 vt BP-t-CM aequaUs ficri poflit "^f (XH~ A) feu 

 quotcunque huiusmodi formularum aggrcgato, nequatio 

 modularis ad difF^rentiaUa fecundi gradus afccndet. 

 Erit enim BP^Af/ji:-|-CM^A(/.v — ^^B^/X -+- BQ_ 

 dadX-hQj^CdX-hCNdadX. Qiiae ert ticquatio 

 modularis quaefita, et iiuiohiit differcntiaUa fecundi gni- 

 dus, quia eam Uttera N ingreditur, qiiae pcr</Q_ide- 

 oque per ddz, ddx et dda detcrminatur. 



§.30. Atfi fuerit BP-f-C M-f-D/) acquaUs huic 

 formulae ^-|-f(X"i-A) vel aggregato quotcunquae hu- 

 iusmodi formularum ; aequatio modularis erit diffcren- 

 tiaU^ tertii gradus, prodibit enim ifta acquatio BP^A 

 ^x-i-CHdAdx-^-BpdAdx^izdBdX -h BQjUd 

 X~\-Q_dCdX-^CNdadX-{-N^DdX-i-DgdadX. 

 Qiiemadmodum ex ante traditis coUigere licet, fi mo- 

 do quantitates ab a tantum pendcntes ad has formu- 

 las accommodantur. 



§. 31. SimiU modo ad altiora difFcrentiaUa pro- 

 greffus f^icile aldfoUiitur. Nam fi BP-t-CM-hDp 



-HEr 



