Bonsoir,
Développer et réduire:
F = (5x - 1)(3x + 4) - (7x + 4)(5x - 1)
F = 15x² + 20x - 3x - 4 - (35x² - 7x + 20x - 4)
F = 15x² + 17x - 4 - (35x² + 13x - 4)
F = 15x² + 17x - 4 - 35x² - 13x + 4
F = 15x² - 35x² + 17x - 13x - 4 + 4
F = -20x² + 4x
Factoriser:
F = (5x + 1)(3x + 4) - (7x + 4)(5x - 1)
F = (5x + 1)(3x + 4 - (7x + 4))
F = (5x + 1)(3x + 4 - 7x - 4)
F = -4x(5x + 1)
Bonne soirée.
