bonsoir à tous j’aurai besoin d’aide uniquement pour les factorisations du 2 de l’exercice 2 merci d’avance

Bonsoir;

a. (x+1)(1-x)-(x+1)(2x+1) = (x+1)[(1-x)-(2x+1)] = (x+1)(1-x-2x-1) = -3x(x+1)

b. 3(2x-2)+(x+1)(1-x) = 6(x-1)-(x+1)(x-1) = (x-1)[6-(x+1)] = (x-1)(6-x-1) = (x-1)(5-x)

c. 2x(x+1)+(x+1)(x²+1) = (x+1)[2x+(x²+1)] = (x+1)(2x+x²+1) = (x+1)(x²+2x+1) = (x+1)(x+1)² = (x+1)³

d. 12x²-6x+(2x-1)(5-2x) = 6x(2x-1)+(2x-1)(5-2x) = (2x-1)[6x+(5-2x)] = (2x-1)(6x+5-2x) = (2x-1)(4x+5)