Bonjour

Factoriser :

A = 25x^2 + 40x + 16

A = (5x)^2 + 2 * 5x * 4 + 4^2

A = a^2 + 2ab + b^2

A = (a + b)^2

A = (5x + 4)^2

B = (3x - 1)^2 - (x - 3)^2

B = a^2 - b^2

B = (a - b)(a + b)

B = (3x - 1 - x + 3)(3x - 1 + x - 3)

B = (2x + 2)(4x - 4)

B = 2(x + 1) * 4(x - 1)

B = 8(x + 1)(x - 1)

C = x^2 - x + 1/4

C = x^2 - 2 * 1/2 * x + (-1/2)^2

C = (x - 1/2)^2

D = (4x^2 - 25) - (2x - 5)(x - 9) - (x + 14)^2

D = (2x - 5)(2x + 5) - (2x - 5)(x - 9) - (x + 14)^2

D = (2x - 5)(2x + 5 - x + 9) - (x + 14)^2

D = (2x - 5)(x + 14) - (x + 14)^2

D = (x + 14)(2x - 5 - x - 14)

D = (x + 14)(x - 19)