Réponses

2014-04-03T19:23:02+02:00
Bonsoir,

1) (2x - 3)(x - 4) + (x + 4)(2x - 3) = 0
(2x - 3) [(x - 4) + (x + 4)] = 0
(2x - 3) (x - 4 + x + 4) = 0
(2x - 3) (2x) = 0
2x(2x - 3) = 0
2x = 0   ou   2x - 3 = 0
x = 0/2   ou   2x = 3
x = 0    ou   x = 3/2

S = {0 ; 3/2}

2) (x - 2)(4x + 5) - (x - 2)(3x - 2) = 0
(x - 2) [(4x + 5) - (3x - 2)] = 0
(x - 2) (4x + 5 - 3x + 2) = 0
(x - 2) (x + 7) = 0
x - 2 = 0   ou  x + 7 = 0
x = 2   ou   x = -7

S = {2 ; -7}