Mathématiques

Question

Help please!! Je n'arrive pas
Help please!! Je n'arrive pas

1 Réponse

  • Exercice 2
    1) * signifie multipllié par
    E = (2x+5)(3x-1)
    E = 2x*3x + 2x*-1 +5*3x + 5*-1
    E = 6x² -2x +15x -5
    E = 6x²+13x-5

    F = (3x-5)²
    F = (3x-5)(3x-5)
    F = 3x*3x +3x*-5 +(-5)*3x + (-5)(-5)
    F = 9x²-15x-15x+25
    F = 9x²-30x+25

    G = (x-1)(x+1)
    G = x*x + x*1 +(-1)*x + (-1)*1
    G = x² +x-x-1
    G = x²-1

    H = (5x+2)²
    H = (5x+2)(5x+2)
    H = 5x*5x + 5x*2 + 2*5x + 2*2
    H = 25x²+10x+10x+4
    H = 25x²+20x+4

    I = (x-3)² + (x+5)²
    I = (x-3)(x-3) + (x+5)(x+5)
    I = (x*x + x*-3 + (-3)*x + (-3)*(-3)) + (x*x + x*5 +5*x + 5*5)
    I = (x²-3x-3x+9) + (x²+5x+5x+25)
    I = x²-6x+9+x²+10x+25
    I = 2x²+4x+34

    2) X=-1
    I = (-1-3)² + (-1+5)²
    I = (-4)² + (4)²
    I = 16+16
    I = 32