§. i8. Nunc vt aream exprimere pofHmus, difFerent.e- 

 mus abfciflam x, et quia coefficientes ad nortrum inftitutuin 

 nihil conferunt, cos protfus negligamus, eritque: 



d X 



__ (tt3-i_|^/^7-f-v-i)3^^ 



I 



(//P-f-W^'^0'' 



Hinc tuitem porro erit clementum areae: 

 j d X :zz ^ 



vl'^ _U ,A -4-|v ' 



(^^l^ 4, ,^1 -4-lv^ — X 



vbi exponens denominatoris .efl; ( ^ v -+- 7 »--+-"■ y -^- »• -^- " q^^| £i.gro 



femper efl: pofitiuus, atque iideo vnitate maior. Vnde fi br. 

 gr. ponamus --_^^it^— _ . — ^, ifte exponens erit i -h^, ntque 

 elementum areae nunc erit: 



du(n^~i-u^^') 

 Y a X — — j^ 4 . 



§. 19. Ante autem qunm noflrum Lemma fupra da- 

 tum huc transferre liceat, tres cafus probe a fe inuicem dis- 

 tingui oportet, prouti fuerit vel i''. y+ ^' > (3, vel '2.". 

 V-i-v'^!^, vcl 3°. Y + ^~H9 \ndQ a poftrcmo, vtpotc 

 /implicidimo, inchocmus. 



OafuS I. quo (^ — y-hv. 



§. co. Hoc cafu fubftitutio adhibitn locum habere pla- 

 ne nequit, propterca quo tam X quam in infmitum excrcs- 

 cerent; verum hoc cafu negotium flne \lla (ubftitutione cx- 

 pediri poteft. Cum cnim aequatio noftra fiat : 



hinc ftatim fit: 



7^ = 



