Bonsoir,
1) G = 4x² - 20x + 25 + (2x - 5)(3x + 4)
G = 4x² - 20x + 25 + (6x² + 8x - 15x - 20)
G = 4x² - 20x + 25 + 6x² + 8x - 15x - 20
G = 10x² - 27x + 5
2) (4x² - 20x + 25) = (2x - 5)²
3) G = 4x² - 20x + 25 + (2x - 5)(3x + 4)
G =(2x - 5)² + (2x - 5)(3x + 4)
G =(2x - 5)(2x - 5) + (2x - 5)(3x + 4)
G = (2x - 5)[(2x - 5) + (3x + 4)]
G = (2x - 5)(2x - 5 + 3x + 4)
G = (2x - 5)(5x - 1)
Exercice 37.
a) 64x² - 25 = (8x + 5)(8x - 5)
b) 36x² - 16 = 4(9x² - 4)
= 4(3x - 2)(3x + 2)
c) 1 - 100x² = (1 + 10x)(1 - 10x)
d) -9 + x² = x² - 9
= (x + 3)(x - 3)
