Réponses

2012-11-11T18:12:39+01:00
2012-11-11T18:14:15+01:00

A= 2x²-3²-(8x²-12x+14x-21)

A = 2x²-9-8x²+12x-14x+21

A= -6x²-2x+18

A= -150 - -10 + 18

A = - 122