Répondre :
F=(x+2)(3x+1)-(x+2)(2x+3)=(x+2)[(3x+1)-(2x+3)]=(x+2)(x-2)=x²-4
(x+2) x [(3x + 1) - (2x + 3)]
= (x+2) (3x + 1 - 2x - 3)
= (x+2) (x-2)
Identités remarquables F=(x+2)(3x+1)-(x+2)(2x+3) Factoriser F
F=(x+2)(3x+1)-(x+2)(2x+3)=(x+2)[(3x+1)-(2x+3)]=(x+2)(x-2)=x²-4
(x+2) x [(3x + 1) - (2x + 3)]
= (x+2) (3x + 1 - 2x - 3)
= (x+2) (x-2)