Réponses

2014-10-04T22:34:28+02:00
Bonsoir Jade.

B = (10x - 5)(3x + 1) - (2x - 1)(x + 7)
B = 5(2x - 1)(3x + 1) - (2x - 1)(x + 7)
B = (2x - 1) [5(3x + 1) - (x + 7)]
B = (2x - 1)(15x + 5 - x - 7)
B = (2x - 1)(14x - 2)
B = (2x - 1) * 2(7x - 1)
B = 2(2x - 1)(7x - 1).

C = (3x + 1)(2x - 1) + (1 - 2x)(x - 3)
C = (3x + 1)(2x - 1) - (2x - 1)(x - 3)
C = (2x - 1) [(3x + 1) - (x - 3)]
C = (2x - 1)(3x + 1 - x + 3)
C = (2x - 1)(2x + 4)
C = (2x - 1) * 2(x + 2)
C = 2(2x - 1)(x + 2).

Voila, bonne nuit !