Bonsoir,
Factoriser:
Identité remarquable différence de deux carrés):
A = (7x + 2)² - (5x + 4)²
A = (7x + 2 - (5x + 4))(7x + 2 + (5x + 4))
A = (7x + 2 - 5x - 4)(7x + 2 + 5x + 4)
A = (2x - 2)(12x + 6)
A = 2(x - 1) * 6(2x + 1)
A = 12(x - 1)(2x + 1) ✅
B = (3 - x)² - (2x + 8)²
B = (3 - x - (2x + 8))(3 - x + (2x + 8))
B = (3 - x - 2x - 8)(3 - x + 2x + 8)
B = (-3x - 5)(x + 11) ✅
* = multiplication
Bonne soirée
