Répondre :
1) G = x² - 6x + 9 - 7x² + 16x + 15 = -6x² + 10x + 24
2) -600000000
3) (x-3)(x-3 - 7x - 5) = (x-3)(-6x - 8) = -2(x-3)(3x+4)
2) -600000000
3) (x-3)(x-3 - 7x - 5) = (x-3)(-6x - 8) = -2(x-3)(3x+4)