Répondre :
(x-1)²+4(x-1)(x+5)
(x-1)(x-1)+4(x+5)
(x-1)(x-1)+4x+20
(x-1)(x-1+4x+20)
(x-1)(5x+19)
(x-1)(x-1)+4(x+5)
(x-1)(x-1)+4x+20
(x-1)(x-1+4x+20)
(x-1)(5x+19)