Réponses

2012-11-19T02:35:02+01:00

(3x+7)[2(4x-5)+(2x-5)] = (3x+7)[8x-10+2x+25] = (3x+7)(10x+15)

(2x+1)[(3x+2)-3(-x+1)] = (2x+1)[3x+2+3x-3] = (2x+1)(6x-1)