FORMVLARVM DIFFERENTIALTVM. 175 



4.. Ob intcgnibi'it:ucm vero rormul.ie : 

 ^V — M dx +^(fj'-\-Vdp-^Qdq .. . .-+-U du 

 quuai efle dcbent 



liquct omniiio efle 



fd X (ii) = fJ .V (fff) ,: idcaque {i|) = g-> 

 Simili modo ob 



fdx[f^)-f<lx fT), ncc non/^.v0=M.v:i-;),erit 



Porro quoniam eft 



(J^)==(2A);f^)^'|^) ctchnbcbitur 

 (i2,:.,/^^(^p-/;^^(^)^^(^)-/^.,(^)::,(g) , 

 (^5=^/''^vC^4)-/^a-(^^pr./-^.v,i-^)-/^.v(f-5)z:: (^^) etc. 

 Dcnique ob (li) — (15.) etc. 

 (l^)^/^.v(lL)L/^x(4)-/rf^<l;)::/^-(4^^ 



Ex bis igitur iam euidenter patet i"d , quod' nobis 

 demonrtrandum propoluimuS', efle nimirum 



Cl^")— (!-*_): (l^ ) — (!'' ) . (±JL\ — (iJl.\ 

 ^dy^^^d X. ■' ^ ^d.p^ Vdx'' Mt ^ — M X '' 



(i-f)=(i-7)i (if )=(fi-) ««^- «<:• 



Perfpi- 



