Question

if alpha and beta are the roots of the quadratic equation x^-2x-7=0 find the value of Alpha^+Beta^

Answer 1

$in \: a {x}^{2} + bx + c = 0 \\sum \: of \:roots = \frac{( - b)}{a} \\ product \: of \: roots = \frac{c}{a} \\ now \: in \: {x }^{2} - 2x - 7 = 0 \\ \alpha + \beta = 2 \\ \alpha \beta = - 7 \\ now \\ { \alpha }^{2} + { \beta }^{2} \\ = {( \alpha + \beta )}^{2} - 2 \alpha \beta \\ = {(2)}^{2} - 2( - 7) \\ = 18$
hope it helps

Answer 2

Answer:

alpha / beta + beta /alpha