Sagot :
7x -14 = 7 * x - 7 * 2 = 7 (x - 2)
35x + 5 = 5 * 7x + 5 * 1 = 5 (7x + 1)
15x + 12 = 3 * 5x + 3 * 4 = 3 (5x + 4)
20x - 25 = 5 * 4x - 5 * 5 = 5 (4x - 5)
x² + 7x = x * x + x * 7 = x ( .. + ...)
6x² + 21x = x * 6x + x * 21 = x (.. + ...)
70x² - 49 = 7 * 10x² - 7 * 7 = 7 (... - ...)
Bonjour
Soit x un nombre. Factoriser les expressions suivantes
7x -14 = 7 * x - 7 * 2 = 7(x - 2)
35x + 5 = 5 * 7x + 5 * 1 = 5(7x + 1)
15x + 12 = 3 * 5x + 3 * 4 = 3(5x + 4)
20x - 25 = 5 * 4x - 5 * 5 = 5(4x - 5)
x² + 7x = x * x + x * 7 = x(x + 7)
6x² + 21x = 3x * 2x + 3x * 7 = 3x(2x + 7)
70x² - 49 = (xV70)^2 - 7^2 = (xV7 - 7)(xV7 + 7)
Ou
70x² - 49 = 7 * 10x^2 - 7 * 7 = 7(10x^2 - 7)