Question

If one of the zeroes of the cubic polynomial x 3 + ax 2 + bx + c is -1, then the product of the other two zeroes is

• A. b - a + 1
• B. b - a - 1
• C. a - b + 1
• D. a - b -1

Answer 1

The correct option is A

b - a + 1

Let α, β be the other two zeroes of the cubic polynomial.
The sum of zeroes of cubic polynomial $x^3+a{x}^2+bx+c$
$\alpha +\beta -1=-a$
The sum of zeroes of cubic polynomial taken two at a time
$\alpha \beta -\beta =b$

$\alpha \beta =b+1-a$