Réponse :
Explications étape par étape
Bonsoir
Factoriser :
A) (x - 1)(x + 2) + 4(x - 1) = 0
(x - 1)(x + 2 + 4) = 0
(x - 1)(x + 6) = 0
x - 1 = 0 ou x + 6 = 0
x = 1 ou x = -6
b) (x - 1) au carrer – 3(x - 1) = 0
(x - 1)(x - 1 - 3) = 0
(x - 1)(x - 4) = 0
x - 1 = 0 ou x - 4 = 0
x = 1 ou x = 4
c) 4x – 1 - 3(2x + 1) = 0. (On ne peut pas factoriser)
4x - 1 - 6x - 3 = 0
-2x - 4 = 0
2x = -4
x = -4/2
x = -2
d) 3x – x au carrer = 0
x(3 - x) = 0
x = 0 ou 3 - x = 0
x = 0 ou x = 3
e) (x + 2)(x – 3) = 6 - 2x
(x + 2)(x - 3) = 2(3 - x)
(x + 2)(x - 3) - 2(3 - x) = 0
(x + 2)(x - 3) + 2(x - 3) = 0
(x - 3)(x + 2 + 2) = 0
(x - 3)(x + 4) = 0
x - 3 = 0 ou x + 4 = 0
x = 3 ou x = -4