Pouvez vous m’aider svp ? A = (4x - 7)(x + 8) C = (5x - 2)(-2x - 1) B= (-2x + 3)(x + 2) D= (3x – 5)2

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A = (4x - 7)(x + 8)

A = 4x^2 + 32x - 7x - 56

A = 4x^2 + 25x - 56

C = (5x - 2)(-2x - 1)

C = -10x^2 - 5x + 4x + 2

C = -10x^2 - x + 2

B= (-2x + 3)(x + 2)

B = -2x^2 - 4x + 3x + 6

B = -2x^2 - x + 6

D= (3x – 5)2

D = 9x^2 - 30x + 25

Explications :

(a - b)^2 = a^2 - 2ab + b^2

(a - b)(c + d) = ac + ad - bc - bd