Anonymous

A cubic polynomial has four variables, so it's not possible to reduce it to an expression made of three variables, except in some particular cases. Probably you've been given some specific equation?

Anonymous

you can't...but any cubic can be written as : a1 (x - b)³ + a2 ( x - b)² + a3 ( x - b ) + a4 , for some values of ai, i =1,2,3,4

Anonymous

Nope It could be y = ax^3+bx^2+cx+d , with a not = 0 or y=a(x-b)(x-c)(x-d) or y=a(x-b)(x-c)^2 or y=a(x-b)^3 + c