gredi oportet^ quia inclinationes planetarum eccentricitati- 

 bus fere funt aequales. 



5- 3 8. Pro evolvendis quantitatibus P, p, habemus 

 valores ellipticos 



r = a [i ■+• y eof ($ — tt) — f cof 2 (£ — tt)] =z a ■+- A r, 

 . r" = a' [1-f-y'cof (t? — 7^) — *2 cof2 (^-tt 7 )] = a'+Ar', 

 V= & — ay fin(£-7r) -+-f y 2 fin2 ($ — tt) — $ -+- A r 5 

 v" = t> — ay^fin (fr-7i / ) -t- | y^ fina (^-tt 7 ) — ^ + A^. 



J. 39. Pofito iam 



laa-\-a' a' — 20^ cof (t> — 6)] ? = j^ 

 1 



et p 2 2zB + AB, cnm p ex quantitatibus r, r', y, p^ 



conftet, per theoriam differentiamm partialium habemus 



. Arf /aaBN + Ar-a / 33B \ Ad» /agB\ A^/^BV 

 2 v da~ ' 2 ^aa'2/ 2 V"d§2/ ~~2 ^817^/ 



-f- Ar A r y (/^U +- Ar Az; (|iJ ) -t- Ar AV* ( ^b y 



^dada" K dad&' ' " ^aa^/ 



-f- Ar' Ai; ( /-^)-+Ar / Az/ / (/-2 ; ) +AvAv" (1*2.), 



quoniam ultra fecundam eccentricitatis dimenfionem non 

 proceditur. 



$. 4-0, Cum itaque fit (§. 3.) 



B = V? cof (* — &)-$ = - A^ eof i (t> - <S), 

 denotante i numerum quemcunque pofitivum, fit 

 /5B\ /dA (z >\ ; J 



