Réponses

2013-12-01T21:35:49+01:00
X*2x-2x-3*2x+3*2-(x^2-2*x*3+3^2)
=2x^2-2x-6x+6-(x^2-6x+9)
=2x^2-2x-6x+6-x^2+6x-9
=x^2-2x-3