Bonsoir,
Factoriser :
A(x) = x^2 + 2x + 1 - (2x + 2)(x + 3)
A(x) = (x + 1)^2 - 2(x + 1)(x + 3)
A(x) = (x + 1)(x + 1 - 2(x + 3))
A(x) = (x + 1)(x + 1 - 2x - 6)
A(x) = (x + 1)(-x - 5)
B(x) = 4x^2 + 4x + 1 - (6x + 3)(x + 1)
B(x) = (2x + 1)^2 - 3(2x + 1)(x + 1)
B(x) = (2x + 1)(2x + 1 - 3(x + 1))
B(x) = (2x + 1)(2x + 1 - 3x - 3)
B(x) = (2x + 1)(-x - 2)