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unde differentiatio perducit ad hanc aequationem: 

 cof. i p cof. $>' x = ( fi -*- g) cof. i p cof. p x - (x/h- g l) fin. i $ cof. $> x " x 

 -g(A-i)cof.t$)rin.$ 2 cof.(!) x - 2 H"/icof.i([)cof.$ x - 2 



Hic iam primo termini, qui continent fin. i(J), tolli debent, 

 unde fit g — — — ? quo valore fubftituto, per, cof. i (J) divi- 

 dendo , poftquam loco fin. (J) 2 fcriptum fuerit i — cof. Cj) 2 , 

 prodit ifta aequatio : 



cof. (J) x = - -^piil cof. (J) x ■+ x / (X - 1 ) cof. $> x - 2 -*- /i cof. (J) x ~ 2 , 



unde manifefto fit f— x ~_^ tl -> hincque % z±s x ^~y , ficque 

 reductio generalis ita fe habebit : 



/ d (J) cof. i ([) cof. (J) x = - ~J . iin. i (J) cof. (J) x 



XX 



H _ xx ^,, cof. (J) fin. £ $ cof. p x ' x 



xjx — i) r^ /ts ^r ; 4> ™r ^ x — 2 

 x a" 



^p$coi:i$cof.(}: 3 



quae faepenumero maximam utilitatem ■ habere poteft; pofi- 

 to autem (J) zzz 7r manifefto prodit elfdtum Lemmatis. 



$. 18. Hoc Lemmate conitituto pro littera D defini- 

 enda fumi debet i — 3 «, eritque 



p CJ) cof. 3 $ cof. (J) x zzz _Al^=ziL_ /a (f) cof. 3 P cof. (J) x ~ 2 ; 



unde ftatim patet, eafibus Xzzzo et Xzz: 1 formulam iftam 

 evanefcere, pofito fcilicet Cf) zzz ix y ita ut fit 



/ d p cof. 3 $ zz: o et fd p cof. 3 <P cof. $ = 0. 

 Hinc autem porro patet, eafu quoque X zz: 2 fore 



/a$cof. 3 (J)cof. C 2 = o. . 

 At vero cafu X = 3 Lemma dabit 



