Réponses

2013-11-03T16:41:44+01:00
D= (x + 2)² - 9
=(x+2+3)(x+2-3)
=(x+5)(x-1) 

E= (-x + 4)² - (6x - 1)²
=(-x+4-6x+1)(-x+4+6x-1)
=(-7x+5)(5x+3)
2013-11-03T17:26:32+01:00
D = (x+2+3)(x+3+2)
D = (x+5)(x-1)

E =(-x+4-6x+4)(-x+4+6x-1)
E = (-7x+5)(5x+3)

voila