[tex] + \frac{9}{3} = + 3 \: \in \: \mathbb{Z} \: \: (A)[/tex]
[tex] + 3 \frac{1}{2} = + \frac{3 \times 2 + 1}{2} = + \frac{6 + 1}{2} = + \frac{7}{2} \: \in \: \mathbb{Z} \: \: (F)[/tex]
[tex]\mathbb{N}=\mathbb{Z_{+}}\:\:(F)[/tex]
Egalitatea era adevărată dacă :
[tex]\mathbb{{N}^{*}}=\mathbb{Z_{+}}\:\:(A)[/tex]
