AIDER MOI POUR MON DM EN MATHS S IL VOUS PLAIT

Salut,

Exercice 1 :

A = (12x+7)² - (11-5x)(12x+7)

1)
A = 144x² + 168x + 49 - (132x + 77 - 60x² - 35x )
A = 144x² + 168x + 49 -(97x + 77 - 60x²)
A = 144x² + 168x + 49 - 97x - 77 + 60x²
A = 204x² + 71x - 28

2)

A = (12x+7)² - (11-5x)(12x+7)
A = (12x+7)[12x + 7 - (11-5x)]
A = (12x+7)(12x + 7 - 11 + 5x)
A = (12x+7)(17x - 4)

3)

A = (12 * (-5/12) + 7)(17 * (-5/12) - 4)
A = (-5 + 7)(-85/12 - 4)
A = 2 * -133/12
A = -133/6


Exercice 2:
B = x² - 8x + 16
B = (x-4)²

C = 36x² + 96x + 64
C = (6x+8)²

D = (5x-3)² - 144
D = (5x-3)² - 12²
D = (5x - 3 + 12)(5x-3-12)
D = (5x+9)(5x-15)
(Niveau seconde) : D = 5(5x+9)(x-3)

E = (9x + 7)² - (4x-15)²
E = [(9x+7) - (4x-15)][(9x+7) + (4x-15)]
E = (9x+7 - 4x + 15)(9x + 7 + 4x - 15)
E = (5x + 22)(13x - 8)

Bonne soirée !