Réponses

2014-09-14T12:48:08+02:00
Bonjour

(x+2)/2) (-x+3) = 0
((x+2)(-x+3)) / 2 = 0
-x² + 3x - 2x + 6 = 0
-x² + x + 6 = 0


identifions a = -1 b= 1 et c = 6

Calculons Δ
Δ = b² - 4ac
Δ = 1² - 4(-1)(6)
Δ = 1 + 24
Δ = 25
√Δ = 5

x1 = (-b-√Δ) / 2a
x1 = (-1-5) / -2
x1 = -6  -2
x1 = 6/2
x1 = 3


x2 = (-b+√Δ) / 2a
x2 = (-1+5) / -2
x2 = 4/-2
x2 = -4/2
x2 = -2


S = {-2;3}