Question

Find a cubic polynomial whose zeroes are 2, - 3 and 4.

• A. $x^3-3x^2-10x+24$
• B. $x^3-x^2-x+2$
• C. $x^3+x^2+x$
• D. $2x^3+x^2+1$

Answer 1

The correct option is A $x^3-3x^2-10x+24$

If a, b and c are the zeroes of a cubic polynomial f(x), then
$f\left(x\right)=x^3-(a+b+c)x^2+(ab+bc+ca)x-\left(abc\right)$
Thus, the required polynomial is:
$x^3-\left(3\right)x^2+(-10)x-(-24)$
$=x^3-3x^2-10x+24$