Réponse :
Explications étape par étape
Bonjour
Factoriser :
4x^2 - 12x + 9
= (2x)^2 - 2 * 2x * 3 + 3^2
= (2x - 3)^2
7x^2 - 28
= 7 * x^2 - 7 * 4
= 7(x^2 - 4)
= 7(x - 2)(x + 2)
(2x - 3)^2 - (5x + 2)^2
= (2x - 3 - 5x - 2)(2x - 3 + 5x + 2)
= (-3x - 5)(7x - 1)
(x - 5)^2 - 2(x - 5)(x - 3)
= (x - 5)(x - 5 - 2(x - 3))
= (x - 5)(x - 5 - 2x + 6)
= (x - 5)(-x + 1)
2x^2 + 7x
= x * 2x + x * 7
= x(2x + 7)
x^2 + 26x + 169
= x^2 + 2 * x * 13 + 13^2
= (x + 13)^2
(9x^2 - 25) + (6x + 10)
= 9x^2 + 6x - 15
= (3x)^2 + 2 * 3x * 1 + 1 - 1 - 15
= (3x + 1)^2 - 16
= (3x + 1)^2 - 4^2
= (3x + 1 - 4)(3x + 1 + 4)
= (3x - 3)(3x + 5)
= 3(x - 1)(3x + 5)
x^2 - 4x + 4 - (x - 2)(7 - x)
= (x - 2)^2 - (x - 2)(7 - x)
= (x - 2)(x - 2 - 7 + x)
= (x - 2)(2x - 9)
