Réponse :
Bonjour,
Rappel:
x*x = [tex]x^{2}[/tex]
x+x= 2x
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L = (5x + 7)(- 4x + 2)
= 5x*(-4x) + 5x*2 + 7*(-4x) + 7*2
= -20[tex]x^{2}[/tex] + 10x + (-24x) + 14
= -20[tex]x^{2}[/tex] - 14x + 14
K = (1 - x)(2x +3)
= 1*2x + 1*3 - x*2x -x*3
= 2x + 3 - 2[tex]x^{2}[/tex] - 3x
= - 2[tex]x^{2}[/tex] - 1x + 3
J = (4 + 2x )(3+x)
= 4*3 + 4*x + 2x*3 + 2x*x
= 12 + 4x + 6x + 2[tex]x^{2}[/tex]
= 2[tex]x^{2}[/tex] + 10x + 12
P = [(x + 2)(x+4)](x+3)
= [ x*x + x*4 + 2*x + 2*4] (x+3)
= ([tex]x^{2}[/tex] + 4x + 2x + 8) (x+3)
= ([tex]x^{2}[/tex] + 6x + 8) (x+3)
= [tex]x^{2}[/tex]*x + 6x*x + 8*x + 3*[tex]x^{2}[/tex] + 3*6x + 3*8
=[tex]x^{3}[/tex] + [tex]6x^{2}[/tex] + 8x + 3[tex]x^{2}[/tex] + 18x + 24
= [tex]x^{3}[/tex] + 9[tex]x^{2}[/tex] + 26x + 24
N = (-4- x)(-3x - 2)
= -4*(-3x) - 4*(-2) -x*(-3x) - x*(-2)
= 12x - (-8) - (-3[tex]x^{2}[/tex]) - (-2x)
= 12 x + 8 + 3[tex]x^{2}[/tex] + 2x
= 3[tex]x^{2}[/tex] + 14x + 8
M= (-6 -5x )( 3x - 2)
= - 6*3x -6*(-2) -5x*3x - 5x*(-2)
= - 18x - (-12) - 15[tex]x^{2}[/tex] - (-10x)
= -18x + 12 - 15[tex]x^{2}[/tex] + 10x
= -15[tex]x^{2}[/tex] - 8x + 12
