URGENT ! Besoin d'aide pour mes exercices Merci ;)

Salut,

Exercice 16 :

A(x) = (2x+1)(x-3) - 4x  + 1
A(x) = 2x² - 6x + x - 3 - 4x + 1
A(x) = 2x² - 9x - 2

B(x) = (4x-5)² = 16x² - 40x + 25

C(x) = 2(x-1)(x+3) = 2[x² + 3x - x - 3] = 2(x² + 2x - 3) = 2x² + 4x - 6

Exercice 17 :

D(x) = (-2x + 1)(x+3) - 2(x-5) = (-2x² - 6x + x + 3) - 2x + 10
D(x) = -2x² - 5x + 3 - 2x + 10
D(x) = -2x² - 7x + 13

E(x) = 3(4x+3)(x+1) + (x+1)²
E(x) = 2(4x² + 4x + 3x + 3) + x² + 2x + 1
E(x) = 2(4x² + 7x +3) + x² + 2x + 1
E(x) = 8x² + 14x + 6 + x² + 2x + 1
E(x) =9x² + 16x + 7

Exercice 19 :

A(x) = (2x + 3)(x-7) + (2x+3)(-4x+5)
A(x) = (2x+3)[x - 7 - 4x + 5]
A(x) = (2x+3)(-3x - 2)
BONUS 2NDE : A(x) = -(2x+3)(3x + 2)

B(x) = (x-1)(2x+4) - (x-1)(x+5) + 2(x-1)
B(x) = (x-1)[(2x + 4) - (x+5) + 2]
B(x) = (x-1)(2x+4-x-5+2)
B(x) = (x-1)(x + 11)

C(x) = (3x+1)² + (3x+1)(2x-4)
ETAPE INTERMEDIAIRE : C(x) = (3x+1)(3x+1) + (3x+1)(2x-4)
C(x) = (3x+1)[3x + 1 + 2x - 4]
C(x) = (3x + 1)(5x - 3)

D(x) = (5x+3)(4x-2) + 2(5x+3)(-x+3)
D(x) = (5x+3)[(4x-2) + 2(-x+3)]
D(x) = (5x+3)(4x - 2 -2x +6)
D(x) = (5x+3)(2x + 4)
BONUS 2NDE : D(x) = 2(5x+3)(x+2)

E(x) = (x+3)² - 3(x+3)(-2x+4)
ETAPE INTERMEDIAIRE : E(x) = (x+3)(x+3) - 3(x+3)(-2x+4)
E(x) = (x+3)[(x+3) - 3(-2x+4)]
E(x) = (x+3)(x + 3 + 6x - 12)
E(x) = (x+3)(7x - 9)

Bonne soirée !