Sagot :
bonsoir,
1) a) A1 = 8x - 6
A1 = 2(4x - 3)
b) A2 = 8x - 6 - (4x - 3 )(2x + 5)
A2 = 2(4x - 3) - (4x - 3)(2x + 5)
A2 = (4x - 3)(2 - 2x - 5)
A2 = (4x - 3)(-3 - 2x)
2) a) B1 = 4x² - 1
B1 = (2x - 1)(2x + 1)
b) B2 = (x - 8)(2x + 1) + 4x² - 1
B2 = (x - 8)(2x + 1) + (2x + 1)(2x - 1)
B2 = (2x + 1)(x - 8 + 2x - 1)
B2 = (2x + 1)(3x - 9) = 3(2x + 1)(x - 3)
3) a) C1 = 25 - 60x + 36x²
C1 = (5 - 6x)(5 - 6x)
b) C2 = (2x + 3)(5 - 6x) + 25 - 60x + 36x²
C2 = (2x + 3)(5 - 6x) + (5 - 6x)(5 - 6x)
C2 = (5 - 6x)(2x + 3 + 5 - 6x)
C2 = (5 - 6x)(8 - 4x) = 4(5 - 6x)(2 - x)