54 DE COMPARATIONE 



vt flt 



19. Vt hnic i:im cufus integrab liratis erua- 

 mus , ponnmus : 



? — a -\- b X -{- c X X -^ d x' -\- e X* 



<^=za -\-by-{- cjj -]-dy'-Y- ef 

 €fitque 



\E^— b-\-c[x-y\-^d[xx-^xy\y:^) + ^ (.vH xxy-\-x)y\y) 

 fiue introdudis nouis Tariabilibus s et t 



^-Ef'^ b -\- c s -\- d 'j s — 1)-\- e s[s s ~ ii). 

 At pro t valore fubftituto babcbimus ob An^" — y 

 P — Q b -\- c s -\- d s s -\- e s' 



A- - j' -^ — ^- —r- ^ — 



vnde confequimur : 



quara formulam intcgrabilcm cflc oportct. 



20 Quo hoc facilius pracflcmus , rccordemur 

 ex § §. 13 ct 14. efle (<J — V)' — a^— XX-a^— p.; 

 (^-y e e^— D/); et ee-y^^^E/) \ndc fit Srz 

 V(jjL-4- 2D/)i--f-E/'X.r^; fuie ex §. 14 et 15. 



Ponamus porro brenitatis gratia : 



b'\-'f:—h; c^—^— — g', d-\—^-~f 



Tt 



