Opuscula . 
i.i — /7^7 * imaginaiia ; adeoque methodus Beilioulliaiia Inu- 
tilis redditur ; fa(flo igitur recurfu ad iioftram., erit pp — i 
— pofitiva, &i dp ■ '■ : ^ ex quo erui- 
dx a — X o ~ a —X 
tur j- r= -r- =: — , Qz s , v p ~ 1 ziz X , , quan- 
titas algebraica jungenda ; coordinatse curvae adliibend^ funt 
X ~ . m 
S . pp ~~ i - — ^ z=zjy , j- . -f- ;v = . X =^ U , Er- 
go pe? noftrum Thcorema erit ?c . 7^— f ^ 
W-x fsldu^ — dy^ ' Caiculus docet fignum pofitivum quanti- 
td^\f\Jdu^ — dy^ effe prsefigendum ; quandoquidem fumptis 
coordinatarum 7, u differentiis refultat """^- k'^ dpc:=.dyt 
& dx = du. Ergo = & = 
2 CT 
, e;ulque raclix •%/ 1 — qq =z ~ . Qlio- 
niam vero ex Theoremate noilro habetur ^du^ — dy^ ~du 
yji — qq^ erit igitur ^ d ti^ - d y"- ^^"^^^ d V^/'"— a;^'" — 
2 ra 3.m ^ m ■. 
D . h , quod argumento ef^ 
•sf dii ~-dy^ fignum affirmativum elTe praeponendum . 
„ ' • - / — ~ — m X d X 
23. Prjs-terea erit D i q q ■ - ^ , atque 
a , a — X 
liide = — -1= , . a — pc , adeoaue 
/ — t 2 OT — i A 
1 —qq — 'm X 
quantitas aJgebraica arcui con;uDgenda = ^ =: -a". 
\/ / ; coordinatK vero funt za^ 
— . ,V 
