Réponses

2014-02-04T21:19:23+01:00
Bonsoir

a) (4 -5x +1)(4+5x -1) = ( -5x +5)( 5x +3)
b) 18x +6 - (49x² -42x +9)
  18x +6 -49x² +42x -9 = -49x² 60x -3
c)(x+1+x+6)(x+1-x-6) = (2x+7)(-5)
d) (2x+1+2x-1)(2x+1-2x+1) = ( 4x)(2)