6)
A = (x + 4)(3 + 2x)
A = 3x + 2x^2 + 12 + 8x
A = 2x^2 + 11x + 12
B = (x - 4)(-8x + 3x)
B = (-8x^2 + 3x^2 + 32x - 12x)
B = -5x^2 + 20x
(B = 5x (-x + 4))
C = (8x + 2)(8x - 2)
Du genre (a + b)(a - b) = a^2 - b^2
C = (8x)^2 - (2)^2
C = 64x^2 - 4
(C = 4 (16x^2 - 1))
D = (4a - 2)(b + 3a)
D = 4ab + 12a^2 - 2b - 6a
(D = 2 (6a^2 + 2ab - b - 3a))
7)
A = (4 - a)^2
A = (4)^2 - 2 * 4 * a + (-a)^2
A = 16 - 8a + a^2
A = a^2 - 8a + 16
B = (b - 1)(b + 1) (idem que C dans 6)
B = (b)^2 - (1)^2
B = b^2 - 1
C = (x + 3)^2
C = (x)^2 + 2 * x * 3 + (3)^2
C = x^2 + 6x + 9
D = (5 + x)(x - 5) (idem que B)
D = (x + 5)(x - 5)
D = (x)^2 - (5)^2
D = x^2 - 25
E = (x - 12)^2
E = x^2 - 2 * x * 12 - (12)^2
E = x^2 - 24x + 144
F = (x + 6)(x + 6)
F = (x + 6)^2
F = x^2 + 2 * x * 6 + (6)^2
F = x^2 + 12x + 36
