bjr
ex 1
Q2
C(x) = (x-3) (x-3) - 4 (x-3) (x+3) car a²-b² = (a+b) (a-b)
= (x-3) [(x-3) - 4(x+3)]
= (x-3) (x - 3 - 4x - 12)
= (x-3) (-3x - 15)
= -3 (x-3) (x+5)
D(x) = -4x (x - 1) + 3 (x + 1) * 5 (x - 1)
= (x-1) (-4x + 15 (x+1))
= (x-1) (11x + 1)
E(x) = (x+4) (x-4) - 7 (x+4) (x+4)
vous pouvez terminer en mettant (x+4) en facteur