Chapter 2 - 2.7 - Inverse Functions - 2.7 Exercises - Page 228: 33

The inverse is not a function.

We have the inverse function: $x=-1,0,1,2,3,4$ and $f(x)= -2,1,2,1,-2,-6$ We need to verify that the inverse is a function. Thus, $f(-1)=-2$ and $f(3)=-2$ So, it has been noticed that for $y=-2$, there are two corresponding values of $x$. Therefore, the inverse is not a function.