JMzfcellanea Curio fa. 1 1 9 



verfed Sine of this be multiplied into Radius 

 or 6 — ir ^3 ir i and taking f of the 

 Log. of the Product, its Cubick Root will be 

 obtained, by which let ^ bb — \ p be divided. 

 I fay, that the Sum of the Quotient and Di- 

 vifor, after the fame manner added to or 

 taken from j b, will give the. Root fought. 

 And the like for the third and fourth For- 

 mula, unlefs that i> bl 4* i bp + \ q is to be 



taken for Radius, and % bb f p into V j bb 



-\-f fi or d\f for the Sine. But thefe 

 Rules will be perhaps better underftood by 

 Examples. 



Suppofe the Cubick Equation z3 ~ 17& 2 + 

 .54*. 350 = 0, and let the Root z. be 

 fought. Here f W is is greater than />, but 

 cj is bigger than the Cube of f b y and there- 

 fore 'tis explicable by one Affirmative Root 



only. Now ** A — f A is and ff * V A f 2 is 

 to be taken for the Sine, to the Radius ^fy- 

 y that is ; and the Arch 



agreeing thereto is 15 0 . 30'. 49". The Log. 

 verfed Sine of this 8.5362376, added to the 

 Log. of the Radius 2.3095913, makes 

 0.8457889, the 3d part of which 0.2819276", 

 is the Log. of the Cube Root 1 .91 394, by 

 which, as a Divifor, dividing -J 2 or ^, the 

 Quotient is 7.37281. The Sum of the Quo- 

 tient and Divifor encreafed by the addition 

 of I is the Root fought, viz.. 14.9534? & c - 



Having thus difpatch'd Cubick, Equations, 

 let us proceed to Biquadratic^ ones. Thefe 

 have always either none, or 2, or 4 true 

 I 4. Roots, 



