Respostas

2013-12-16T19:48:58-02:00
(x + 1)(x - 5) = 0
x² - 5x + x - 5 = 0
x² - 4x - 5 = 0

Δ = (- 4)² - 4 . 1 . (- 5)
Δ = 16 + 20
Δ = 36

x = - (- 4) +- √36 / 2 . 1
x = 4 +- 6/ 2

x' = 4+6 / 2 = 10/2 = 5
x" = 4 - 6 / 2 = -2 / 2 = -1

S = {5,-1}