) 247 ( ^n^" 



parabolae eft x: rr 1 , quaeramus pdmo aream 11 S Z, 



^ cof. ^ vj^* ' ^ ^ 



quam defignemus per 2E, ita vt fit a' S — 5 ^ 2 ^ ^4^ , eriique 



^2 = 



Ippd^ 



cof. ^ vi>* 



Ad hanc formulam integrandam flatuamus tang. \^ —t^ 

 eritque 



fin- 5 ^ = jttxtk et cof. ; vj^ =: 



et \d \\/ — p:~7-^, ideoque habebimus 



vnde integrando nancifcimur aream '^—ppt-\-\ppt% 

 cxiftente fcilicct t — tang. 5 \\/, 



§. 8. Hinc autem facile deriuatur altera area 

 n S Z', quam vocemus — X', fi modo in formula praece- 

 dente loco \\/ fcribamus i8o°->4>', ideoque loco 5 \l/ fcribendum 

 crit 90° — 5 v^, cuius tangens cum fit cot. 3 v^» — J, ftatim re- 

 peritur area ifta 2' =: ^ 4- tt., His igitur duabus areis 

 iungendis coUigitur tota area 



znz> = s-^-hX'-fj(tt-\-iy. 



Cum igitur fit S — ^ ( 'J-±-' }% angulum 4* iterum intro- 

 duccndo erit 



3 Vm. i vi^ cof. 1 >V-' 

 S — ^ /-1-^' — 'pp 



« • Vjiin.vt/ ""■j/m.vJ/J/ 



f 9' 



