Mathématiques

Question

Bonjour j’ai besoin d’aide svppp

N = 2x2 + 3x
0 = (3x + 2)(4x + 2) + (3x + 2)(2x - 8)
P = 25x2-9
Q = (7x + 4)(-4x + 2) - (7x + 4)(-3x + 7)
R = (3x + 2)2-(3x + 2)(7x+ 5)
S = (-3x - 2)2 - (7x + 3)2

1 Réponse

  • bjr

    N = 2x² + 3x = x * 2x + x * 3 = x (2x+3)

    0 = (3x + 2)(4x + 2) + (3x + 2)(2x - 8)

    0 = (3x+2) [(4x+2) + (2x-8)]

    0 = (3x+2) (4x+2+2x-8)

    0 = (3x+2) (6x-6)

    0 = 6 (3x+2) (x-1)

    P = 25x² - 9 = (5x)² - 3²

    = (5x+3) (5x-3)           puisque a² - b² = (a+b) (a-b)

    Q = (7x + 4)(-4x + 2) - (7x + 4)(-3x + 7)

    voir le 0

    R = (3x + 2)2-(3x + 2)(7x+ 5) = (3x+2) (3x+2) - (3x+2) (7x+5) => voir le 0

    S = (-3x - 2)² - (7x + 3)² => voir le P

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