The given binomial expression is:
[tex]2z^4-2[/tex]The common factor is 2.
Hence, we factor out 2
[tex]2z^4-2=2(z^4-1)[/tex]We then apply the diference of
Therefore, the factored answer is
[tex]\begin{gathered} 2(z^4-1) \\ =2(z^2-1)(z^2+1) \\ =2(z-1)(z+1)(z^2+1) \end{gathered}[/tex]