Given the expressions:
[tex]\begin{gathered} z^3 \\ 3z \end{gathered}[/tex]these two expressions are not equivalent, since one is thrice a number and the other is a cubic number. We can see this if we write completely each expression:
[tex]\begin{gathered} z^3=z\cdot z\cdot z \\ 3z=z+z+z \end{gathered}[/tex]thus, the expressions are not equivalent
