) 23 ( ^?€<- 



5 = 7—7-^, ideoque valor nofter qiiaefitiis erit 



k cof. '-l;^ 



2k 



vnde iiafcitur fequen: 



Theorema i. 



§. 24. iy?^ formula integraiis : 



I -H :c ' '^ X 



a termino .v — o vsque ad terminum x — 00 extenfa , pro^ 



dueit hunc i:alorem: -, — 7-.1; , cuius demonltratio ex prae- 

 k cof. l^ ^ 



cedente paragrapho liquet. Huic adiungi poted fequens 

 Thcorema, quod piorfus fingulari demonfiratione ex ifto de» 

 riuare licet. 



Theorema 2. 



§. 25. Si tam ifla formulaintegralis-f— .— 



i +a"' X ' 



x^-^"^ dv 

 quamhaec: f~ -^ , a termlno x — o vsque ad x—00 



txicndatur, iHraqiie producet eandem fummam, quae efl 



1'kTof^' 



Demonftratio. 



Ponatur Szizf- ^.— , fiquideni inteeratio a 



tcrmino .v ~ o vsque ad terminuni x — 00 extendatur, ac 



pona- 



