V (i -H3 n) 



_^4(i~ x») 



i — x 

 quibus fubftitutis prodit 



, v _ T y (* — ; x) a x 



2/4 (1 -4- x 3 ) y (1 — x 3 ) 



$. 13. Hoc modo formula inuenta vltro in duas 

 partes discerpitur, atque integratio hoc modo repraefentari 

 poteft : 



*, r ^x r xxdx 

 a v/ + = / ; -/ 3 • 



(i-+-x 3 )/(i-x 3 ) J (l-hX 3 )}/(l-X 3 ) 

 quarum formularum prior ad rationalitatem perduci poteft, 



ponendo =z t, ita Vt pars prior fit/- '^ : tum 



^(1-x 3 ) 

 autem erit x 3 = t 3 — t 3 x 3 , ideoque x 5 = ^^ , vnde ftatim 

 fit i+i s ~ ^"tt • Sumtis autem logarithmis differentian- 

 do colligitur ^ = t d J_ t3) ficque pars ifta prior euadet 

 f-*i— 9 cuius integratio eft in promtu. 



J. 14. Partis pofterioris tra&atio adhuc magis eft 

 obuia. Pofito enim V ( 1 — x 3 ) = u, fit x 3 = 1 ■ — u 3 , tum 

 vero x x d x = — uudu et i-j-x 3 =2 — u 3 j hoc ergo 

 modo habebitur 



/x xd x f udu 

 3 J r> 7.3 * 



(l-f x 3 )/(i-x 3 ) u 



Noua Acla Acad. Imp. Scient. Tom. X. D To» 



