[tex]( - 1) {}^{2} = 1 \\ ( - 1) {}^{3} = - 1 \\ ( - 2) {}^{3} = - 2 \times 2 \times 2 = - 8[/tex]
Minus la putere pară devine plus.
Minus la putere impară rămâne minus.
[tex]a = ( - 1) {}^{2} + ( - 1) {}^{3} + ( - 2) {}^{3} \\ a = 1 + ( - 1) + ( - 8) \\ a = 1 - 1 - 8 \\ \boxed{a = - 8}[/tex]
