Réponses

2012-10-18T18:55:15+02:00

a) (x-3)(2x+3-x-4)=(x-3)(x-1)

b) (-x+5)(x-1)+(2x-3)(-x+5)=(-x+5)(x-1+2x-3)=(-x+5)(3x-4)

c) (2x-3)²-(x+5)²=(2x-3-x-5)(2x-3+x+5)=(x-8)(3x-2)