) O C S 
2:o Si Sio. x . Cof. v. Cof. y esfet evolvendus, 
Fs&or Cof. v. Cof. y invenitur per Prop. 2^ & 
illius valor duâus in Sin. x per Prop. i. 
3:0 Per fimilem applicationem propofitionum 
4:0 Cof. î) + x = Cof. v. Cof. x — Sin. v . 
Sin. x, nec non Sin. u-fx = Sin. v Cof. x -+• Sin. x. 
Cof. v . 
PROP. 4. 
Integrare quantitatem differentialem dv. Cof. v. 
Radio AC ~ 1, (Tab. XI. Fig. 2.) defcribatur 
circulus Pj 5 C. Sic arcus C 7 / = u, differentiale illius 
arcus HG = i©, = Sin. v, AE ~ Cof. v. Du- 
catur GD parallela ipfi HE , & HI normalis ad 
GD. Ob fimiiia triangula GHl & AHE erit GH: 
Gl : : AH : A E, hoc eft dv : GI : : 1 : Cof v , unde 
G/ = dv . Cof. v. Eft vero G 7 differen iale Sin. v 9 
cujus integrale eft: Sin. v , ergo Sin. v = Jdv. Cof. v . 
Cor. i. Differ. Sin. v = dv. Cof. v . 
Sin. « -f- m.v 
n 4- m 1 
Cor. 2 Jdv. Cof. m + n . v = m 
pofitis pro m Sc n numeris quibuslibet. 
PROP. j. 
Integrare quantitatem differentialem dv. Sin. v . 
Stantibus iisdem ac in propofitione praecedenti, 
erit GH : HI : : AH: HE, hoc eft dv : HI : : 1 : Sin. v 9 
unde dv. Sin. v = HI = — ■ differ. Cof. v . Hinc 
Jdv. Sin. v = — Cof. + Pofito autem v == o, 
erit 
