Mulțimea numerelor întregi se notează cu [tex]\large \bf \mathbb{Z}[/tex] si cuprinde numerele atat pozitive cat si cele negative:
[tex]\large \bf \mathbb{Z} = \big\{.... -3, -2, -1, 0, +1, +2, ......\big\}[/tex]
[tex]\bf A = \bigg\{2, -4, \dfrac{15}{5}\bigg\}[/tex]
[tex]\bf B = \bigg \{\dfrac{21}{3}, -\dfrac{11}{11}, 2 \bigg\}[/tex]
[tex]\bf C = \bigg \{\dfrac{21}{3}, 2,7\bigg\}[/tex]
[tex]\bf\dfrac{15}{5} =\dfrac{3}{1}=3\\\\\\\bf-\dfrac{11}{11}=-1\\\\\\\bf\dfrac{21}{3}=\bf\dfrac{7}{1}=7[/tex]
Bafta multa !