50 DE I NTEG RAT I0N E 



§. 25. Veram mifili membrorum difparitate for- 

 mationem parium membrorum generahus concipiumus, 

 pjnatar ergo : 



(1) az= cL-+-2p(x-\-y)-\-y(xx-\-yy)-\-2$xy-\-2exy(x-\-y) 



-\-\xxyy 

 vnde diflferentiando obtinetur: 



dx( (3 -\- y x -\- Sy -f- * e xy -4- e vy-\-%xyy)-\-dy(p-\-yy 

 4- £#4- 2 exy -\- ex x -\- % xxy)~ a 

 ideoque 



/„\ d_y ._ — dx 



* / fi-i-y-x:-h$j-i--Z.*ji-i-eyy-i-£xyy fi-i-yy-+-$x-hzzxy-t-£j.x-h£xxy 



Ex reiolutione autem aequationis atTumtae ehcitur. 

 Ponatur breuitatis gratia 



eritque 



P 4- $x-\-exx-\-yy-\- 2e^4-$wryr__V(A4- 2 Bx4- Gre 



§-\-$y-\-eyy-\-yx-\-2exy-\-%xyyz:~^V(A-\-2By-\-Cyy 



4-2D/ J -+-Ej^) 



§. 26. Hinc itaque concludimus huius aequationis, 

 differentialis : 



dx_ dy 



V (A -j- t BxHhC.s3e-t-*D;c. 5 -fc.Ex*) Y(A-^2By-+-CjjH-?Dy I -f-Ey+) 



aequationem integralem eamque completam e(fe 

 *>-«+ 2 P(*+^)-f y (xx+jy)-\-2$xy-\r2exy(x-\-y)-\-%xxyj 



adkv- 



