A cura di: Alfredo Bochicchio

1)$3ab+9a^2$=3a(bxx3a)$

2)$9x^4-6x^3=3x^3(3x-2)$

3)$y^4xx1/2y=y(y^3xx1/2)$

4)$5a^3+15a^2=5a^2(axx3)$