8a ELEMENTA 



variatio, vsque ad terminum xz=:a extenfa, femper ex- 

 primetur hoc modo •. 



, I^ z' z' D N ^( CL) , d d(_R ) d» ( S ) V 



4-?f(((i)-'-il^ + '^-etc.) 



•f'^((R)-'dtf^H-ctc.) 



+ '^^((S)-etc.) 



fumto elemento dx conftante. Qiiemadmodum autem- 

 litterae ( N) , (P) . ( Q. ) , (R) , (S) etc. fe habeant , id 

 quouis cafu patebit. 



C a fu s I. 



54.. Si dZzUdxi-Ndj-hVifp+Qdq-hKdr-^-Sds etc. 

 erit 



(N) = N; (P):=rPi (Q) = Q; (R) = Rj (S)=Setc. 



Cafus ir. 



55. Si dZ-Ldni-Mdx-\-N4y+?dp-hQdq+Kdr-{-ctc. 

 exiftente U—f^dx, et 



</3-§9J^.v-hgi^^j'-f-q5fl'p-hD^^+3l^r-i-etc. 



fit fLdxz=:W f ac pofito Arrrtf, fiat W = A , quo 

 fa(5to erit: 



(N)=:N^-(A-W)?)^ 



(q)--(^-i-(A-W)D 



(S)=S-i-(A-W)e 



(P)z=P-i-(A-W)qj 



(R)=:R-i-(A-W)3l 

 etc. 



Cafu» 



