Answer :
The expressi
[tex]y=x^2-1[/tex]and we would like to know the domain and range of the function. Since for every x value we give to the equation the result will always be a real number the domain of this function is
[tex]\text{dom y=(-}\infty,\infty)[/tex]Now to find the range of the function we solve the equation for x.
[tex]\begin{gathered} y=x^2-1 \\ x^2=y+1 \\ x=\pm\sqrt[]{y+1} \end{gathered}[/tex]This root will only exist if
[tex]\begin{gathered} y+1\ge0 \\ y\ge-1 \end{gathered}[/tex]Therefore the range of the function is:
[tex]\text{range y=}\lbrack-1,\infty)[/tex]