Réponses

2012-11-28T20:46:49+01:00
2012-11-28T20:48:33+01:00

B = 7x²+21x-4x-16 + (49x²-7x-28x+4)

= 7x²+21x-4x-16+49x²-7x-28x+4

= 56x²-39x-12

 

(7x+4)(8x+3) = 56x²+21x+32x+12 = 56x²+53x+12