/: 



hoc eft 



Cum igitur fit 



integrali ita fumto, \t euancfcat pofito j' — o, erit arcui 

 iiofter 



DZrzjf — 3p + 3|/(PP + 3pr),' 

 hincque D N — D Z — - 3 /). Hinc cum fit arcus AD zzz 2/>, 

 crit etiam DN — ADZ — />. 



Corollarium g- 



§. 12. Quin etiam, fi in axe AB finiftrorfum pro- 

 dut^lo capiatur intcruallum A I zr: A C =1 i/>, atquc in 1 erl- 

 gatur perpcndicuium 1 T, tangenti ZT occurrens in T, ar- 

 cus indefinitus A D Z acquabitur \bique femifummae perpcn- 

 diculi et tangentis, quod ita oftcndo. Du«fta ZQ axi paral- 

 lela erit 



Z V: Vf— ZQ:QT 



ZV:Zf r^ZQ.ZT, 



vnde fit 



7. t . y.Q^ Sjj3_p_-h y) 



"z V d y 





ideoque 



QT -[- Z T in ( 3 p -^iy u 3 x-4-ds) ^ 

 d y 



Tum vcro habcbimus cx §. 11. 



(ll-p-xzizlll^V(PP'\-lPj)^ 



nec 



