Bonsoir,
Factoriser les expressions
C= 4(1-6x)(7x-2)+9(x-3)(7x-2)
C = (7x - 2)[4(1 - 6x) + 9(x - 3)]
C = (7x - 2)(4 - 24x + 9x - 27)
C = (7x - 2)(-15x - 23)
D= (5x-8)² - (2x+9)²
D = a² - b²
D = (a - b)(a + b)
D = (5x - 8 - 2x - 9)(5x - 8 + 2x + 9)
D = (3x - 17)(7x + 1)