Question

deltra 2x ao quadrado +x -1=0

Answer 1

2$x^{2}$ + x-1=0
Δ=$1^{2}$ -4.2.(-1)
Δ=1+8
Δ=9

Answer 2

2x² + x - 1 = 0
a = 2
b = 1
c = - 1

∆ = 1² - 4 × 2 × (- 1)
∆ = 1 + 8
∆ = 9

X = (- 1 ± √9) / 2 × 2
X = (- 1 ± 3) / 4

X' = (- 1 + 3) / 4
X' = 2 / 4
X' = ½ ou 0,5

X" = (- 1 - 3) / 4
X" = - 4 / 4
X" = - 1

S = {- 1, ½}