Question

if alpha and beta are the zeros of the quadratic polynomial aX square + bx + c then find the value of Alpha + beta + alpha beta​

Answer 1

$if \: \alpha \: and \: \beta are \: zeros \: of \: poly \\ a {x}^{2} + b {x} + c \\ then \: \\ \alpha + \beta = - \frac{b}{a} ..............1 \\ and \: \alpha \beta = \frac{c}{a} \\ therefore \: value \: of \alpha + \beta + \alpha \beta \\ = - \frac{b}{a} + \frac{c}{a} \\ = \frac{ - b + c}{a} \\ = \frac{c - b}{a}$