Réponses

2014-01-12T13:32:50+01:00
A=(x-1)²+x²-1
=(x-1)(x-1)+(x-1)(x+1)
=(x-1)(x-1+x+1)
=2x(x-1)

B=3x-3+x-1
=3(x-1)+(x-1)
=(x-1)(3+1)
=4(x-1)