Factoriser f et g f(x)=x2-9-(x+3)(7x-14)-2(x+3) g(x)=(3-2x)2+(2x-3)(1-2x) Merci d’avance !

Bonjour,

Factoriser:

f(x)=x²-9-(x+3)(7x-14)-2(x+3)

    = (x-3)(x+3)-(x+3)(7x-14)-2(x+3)

    = (x+3)(x-3-7x+14-2)    

    = (x+3)(-6x+2)

    = - 3(x+3)(2x-3)

g(x)= (3-2x)²+(2x-3)(1-2x)

     = (3-2x)(3-2x)+(-3+2x)(1-2x)

     = (3-2x)(3-2x)-(3-2x)(1-2x)

     = (3-2x)(3-2x-1+2x)

     = (3-2x)(2)

     = -2(2x-3)