Réponse :
Bonjour
A = 6x + 3 + 4(2x + 1)² = 3(2x + 1) + 4(2x +1)²
A = (2x + 1)(3 + 4(2x + 1)) = (2x + 1)(3 + 8x + 4)
A = (2x + 1)(8x + 7)
B = 2(5x - 1)² + 10x - 2 = 2(5x - 1)² + 2(5x - 1)
B = 2(5x - 1)(5x - 1 + 1) = 2(5x - 1)(5x)
B = 10x(5x - 1)
C = (x² - 4) + (x + 2)² = (x - 2)(x + 2) + (x + 2)²
C = (x + 2)(x - 2 + x + 2)
C = 2x(x + 2)
D = 36x² - (5x + 1)² = (6x)² - (5x + 1)²
D = (6x + 5x + 1)(6x - 5x - 1)
D = (11x + 1)(x - 1)
E = (4x - 3)² - 25x² = (4x - 3)² - (5x)²
E = (4x - 3 + 5x)(4x + 3 - 5x)
E = (9x - 3)(3 - x)
F = 49 - (5x + 2)² = 7² - (5x + 2)²
F = (7 + 5x + 2)(7 - 5x - 2)
F = (5x + 9)(5 - 5x)