Question

If two of the zeros of the cubic polynomial $a{x}^3+b{x}^2+cx+d$ are 0 then the third zero is

(a) $\frac{-b}{a}$ (b) $\frac{b}{a}$ (c) $\frac{c}{a}$ (d) $\frac{-d}{a}$

Answer 1

Let the required roots be p ,q ,r
let the two roots let p and q be 0 (given)
we know that$\to$ sum of roots = -b/a
$\to$ p + q + r = -b/a
$\to$ 0 + 0 + r = -b/a
$\to$ r = -(b/a)
so option a is correct