Question:
If α and β are the zero of x2 + 5x + 8, then the value of (α + β) is
(a) 5
(b) −5
(c) 8
(d) −8
Solution:
(b) $-5$
Given: $\alpha$ and $\beta$ are the zeroes of $x^{2}+5 x+8$.
If $\alpha+\beta$ is the sum of the roots and $\alpha \beta$ is the product, then the required polynimial will be $x^{2}-(\alpha+\beta)+\alpha \beta$.
$\therefore \alpha+\beta=-5$