Réponses

2014-10-05T20:36:44+02:00
5x^2 + 5x - x -1 = 22/5

5x^2 + 4x -1 = 22/5    5x^2 + 5x - x -1-22/5 = 0

5x^2 + 5x - x -27/5 = 0

Δ = 25 - 4*5*(-22/5) = 25 + 88 = 113

x1 = -5+√113  / 10

x2 = -5-√113  / 10
2014-10-05T21:08:21+02:00
On le fait comme ça courage!!
5x^2 + 5x - x -1 = 22/5
5x^2 + 4x -1 = 22/5    5x^2 + 5x - x -1-22/5 = 0
5x^2 + 5x - x -27/5 = 0
Δ = 25 - 4*5*(-22/5) = 25 + 88 = 113

x1 = -5+√113  / 10
x2 = -5-√113  / 10