Respuesta :
[tex]\frac{1}{z^{-3}}[/tex]
Multiply numerator and denominator by z^3:
[tex]\frac{1}{z^{-3}}=\frac{1}{z^{-3}}\times\frac{z^{3}}{z^{3}}=\frac{z^{3}}{1}=z^{3}[/tex]
Multiply numerator and denominator by z^3:
[tex]\frac{1}{z^{-3}}=\frac{1}{z^{-3}}\times\frac{z^{3}}{z^{3}}=\frac{z^{3}}{1}=z^{3}[/tex]