Bonjour
Développer et réduire les expressions suivantes en utilisant les identités remarquables dès que possible :
A = 2x(5x + 3) = 10x² + 6x
B = (2+7x) - 406x - 1) --> Erreur
C = (x - 5)² = x² - 10x + 25
D = (2x + 4)² = 4x²+ 16x + 16
E = (8x - 3)(8x + 3) = 64x² - 9
Factoriser:
A = 36x² - 24x = 12x (3x - 2)
C = (5x - 1)(9x - 4) - (7x + 4)(5x - 1)
C = (5x - 1) [(9x - 4) - (7x + 4)]
C = (5x - 1) (9x - 4 - 7x - 4)
C = (5x - 1) (2x - 8)
C = 2 (x - 4) (5x - 1)
E = x² - 49 = (x - 7) (x + 7)
B = 4x(x + 3) + (x+3)(3x - 11)
B = (x + 3) (5x - 11)
D = x² + 6x + 9 = (x + 3)²
F = -20x + 25 + 4x² = (2x - 5)².
