Question

Y=2x²-128 raizes reais

Answer 1

Para achar as raízes, basta igualar "y" a zero.

y = 2x² - 128 
2x² - 128 = 0
2x² = 128
x² = $\frac{128}{2}$
x = $\sqrt{64}$
x = 8   ou  x = -8

S{-8 , 8]

Answer 2

2x² - 128 = 0
2x² = 128
x² = 64
x = ± √64
x = ± 8


S = {-8, 8}