404. D E M O T V 



ac dcniiuc ob y :=:('] p erit 



« - -^l r": (S + c-t) + f, r': (S+ct) 

 + lA":iS-ct)-i-^A':{S-ct). 



Hinc cr^o pro ftatu initiali poncnJo t — o aJi- 

 pilcimur ; 



'V^^JSSdSl'^-k{r':S-\-A':S)-i-^^<r:S+A:S) 



^ = Q(i-/§=-hs(r":S-|-A'':S') 



H = - £ (r" : S - A" : S) 4- /- T' : S - A' : S). 



Ciim igitur tum fucrit-y — o, ^ — Q^ ct y = T, 

 fcqMcntes niincifcimur aequationes ex quibus naturain 

 bin.irum fundionum r et a definiri oportet 



I. fSSdSl^ -S(r':S-fA':S)H-r:S-i-A:S = o 



II. S/|=r":S4- A":S 



III. ^SST=-S'r":S-A":S)-f-r':S-A':S 



quarum prima diffcrentiata cum fccunda conuenit , 

 •vti quidem rei natura pollulat , ita vt duabus tan- 

 tuni cond tionibus fit fatibfacicndum. Ponamus bic- 

 ■vitatis gratia : 



r';S-HA': S— > et r':S-A':S — ^ vt flat 



II. S(iS/^-dj ct III. lSSr(/S~-Sdz-{-zdS 



hincque 

 y-fSdS/f ct -l-l/rdS fcu zr:z^jrdS 



vudc 



