Dadas as afirmativas a seguir:

1. I. $x^5-1=(x^2-1)(x+1)(x-1)$
   

2. II. $x^5-1=(x-1)\left(x^2+\frac{1-\sqrt{5}}{2}x+1\right)\left(x^2+\frac{1+\sqrt{5}}{2}x+1\right)\left(x^2+\frac{1+\sqrt{5}}{2}x+1\right)$
   

3. III. $x^5-1=(x^3+1)(x^2-1)$
   

4. IV. $x^5-1=(x-1)(x+1)(x-1)(x+1)(x-1)$
   

Quantas são verdadeiras: