MtfceUanea Curio fa. 73 



*ne is much greater than ate, the quantity—^— 



will not much exceed e fo that putting 



b b 



e ~ — then the quantity (to which 



$aa $aa^$ae 



e is nearly equal) will be found 



b b , . ab 

 ~ — or — that is — r , ~ e 



$aa-\-$dv ^aa-yb $aa\>b 



$aa ! i* 



And fo the fide of the Cube a a a \ $ will be 

 a \ f, which is the Rational Formula of 



M. ife Lagney. But now, if were the next 

 greater Cubick Number to that given, the fide 

 of the Cube a*a—b, will after the fame man- 



ab 



ner be found to be a , . And this eafy 



%aa — b 



and expeditious Approximation to the Cubick 

 Root, is only (a very fmall matter,) erroneous 

 in point df defeUj the quantity <?, the remain- 

 der of the Root thus found, coming fomething 

 lefs than really 'tis. 



As for the hr at ionaU Formula 'tis deriv'd from 

 the fame Principle, vi z.. bzz % aae^t$me^ ox 



— — aeA r ee 1 and fo V I A J — and 

 3 a 3 a 



y^aa±A ^a^.a^re A the Root fought. Alfo 

 3^2 



the fide of the Cube aaa—b, after the fame 

 manner, will be found to be 5^Yf^4^-ii. 



And 



