Bonjour
factoriser x⁴-2(x+1)²+4x+3
= x^4 - 2(x^2 + 2x + 1) + 4x + 3
= x^4 - 2x^2 - 4x - 2 + 4x + 3
= x^4 - 2x^2 + 1
= (x^2)^2 - 2 * x^2 * 1 + 1^2
De la forme : a^2 - 2ab + b^2 = (a - b)^2
= (x^2 - 1)^2
De la forme : a^2 - b^2 = (a - b)(a + b)
= [(x - 1)(x + 1)]^2
= (x - 1)^2(x + 1)^2
