Réponses

2013-12-18T14:25:05+01:00
A= (x+1)² - (x-1)²
=x²+2x+1-(x²-2x+1)
=x²+2x+1-x²+2x-1
=4x
2013-12-18T16:45:37+01:00
A= (x+1)² - (x-1)²
A= x²+2*x*1+1² - (x²-2*x*1+1²)
A= x²+2x+1-x²+2x-1
A= 4x