->I4€ ) »48 ( S-ff"*- 



§. 2. Aequatio propofita, pofito s—pq, jndiiet 

 formam fequentem 



dp{i-p)(nn-ppqq)^{pdq-\-qdp){nn-Vp'+ppq-Vfq)-0 

 quae adu euoluta dabit 



nndpii - p) -\-p d p{nn -h p' -^ pp q-h p' q) 

 ^qdp {n n -i-p' ■+■ zp'q) =zo. 

 Cum in yltimo membro occurrat p' -f- 2 p* ^ , ftatuatur 

 ii^2q]pp = tt, \t iit /,zz^_i 

 <f f t d q 



dt tdq_ t d t ttdq 



nn^f-^-ppq + rq^nfi-^—h 

 t' t' q 



^ i4- 1 et 



(>^+if (2^+1)' 

 nn-^-p^^^rqzznn-^j^-^: 



Hls valoribu» fubftitutis habebitur 



nndt{t-\-q) nntdt nntqdq: nnttdq qt^dt 



t^dq fqdq 



Ordinetur aequatio fecundum differentialia quantitatum va- 

 riabilium, et prodibit 



nn 



