53 



2a-f-§=::o; 2|3-f-a-f-î = o; 2y4-(3^|a 4-5^2 = 0; 

 2 5 -Hy-H|(3-(-|a^i=io; etc. 

 imde prioves saltem Iiterae has recipiunt deteiminationes: 

 « = ~i; ^ — o; Y = u, S — o; etc. 

 §. 16. Quo autem hos valores facilius investigemus, 

 consideremus hanc seriem : ^ 



V =z|H-az + Pz' + Vz' + etc. 

 cujus scilicet summam V quaeri oporteat. Inde ergo se- 

 quentes derivemus séries: 



2V=i:i-)-GazH-2^zz-i- Gyz' -+- 2 5z* -f- 2e2^ -4- etc. 

 Vz= ^|ZH-azz-+-(3z'-f- yz-» H- S%^ -f- etc. 

 2 Vzz zz: — H- ï -Hïa-f.ip_Hiy-f- etc. 

 îVz' = — — ^i +ia+îp+ etc. 



iVz* = — — — ^i -^i a H- etc. 



etc. 

 Hariira igitur serierum siimma, ob aequalitates ante allatas, 

 fiet :=:!_, sicque habebimus istani aequationem : 



V(2+Z-hi2*-f-,i2'+ r^^Z^-hetC.)^!. 



Quare ciim sit 



e^ =: 1 -F z + ï z^ + I z^ + etc. 

 erit manifesto V (1 -f- é^) =1 i, sive V=r^-q^, unde fit 



1 -f- e* 



5^. 17- Ponatar igftar ut ante '^^ = M , ut sit 



-, . . . • ■ j -— f 



2 V =z 1 — u, sitque iteruiiï z rr 2 1, ita ut u zn , et 



