Question

Find the values of p for which the quadratic equation 2x^2+px+8=0 has real roots.

Answer 1

2x^2+px+8=0

for real root

$b^2$-4ac >0

$p^2$-4.2.8 >0 ( here substitute b for p as in the givien equation )

$p^2$ - 64 >0

$p^2$>64

$p>\pm 8$