Réponses

2013-03-14T10:39:01+01:00

a = 81 -90x+25x²

b = -8+32x+x-4x² = -4x² +33x-8

c = -9 (12+8x-18x-12x²) = -9(-12x²-10x+12) = 108x²+90x-108