Question

como resolvo isso?
 determine as raizes reais da equaçao x2-16=0

Answer 1

Resolvendo por $x = \frac{-b \pm \sqrt{b^2 -4*a*c}}{2*a}$

$x^{2} -16 = 0$

a=1, b=0, c=−16
Δ=b2−4ac
Δ=(0)2−4*(1)*(−16)
Δ=0+64
Δ=64

$x = \frac{-b \pm \sqrt{\triangle}}{2*a}$

$x = \frac{0 \pm \sqrt{64}}{2*1} \\ \\ \ \\x = \frac{0 \pm 8}{2}\\ \\x = \frac{0 + 8}{2}\\ \\x = \frac{8}{2}\\ \\x' = 4 \ \\ \\ \ \\ x''= \frac{0 - 8}{2}\\ \\x'' = \frac{-8}{2}\\ \\x'' = -4$

S ={4, -4}