Chapter 4 - Exponential and Logarithmic Functions - Section 4.2 One-to-One Functions; Inverse Functions - 4.2 Assess Your Understanding - Page 290: 9

The range of the inverse is $[4, \infty)$.

We know that the function and its inverse have the $x$ and $y$ interchanged. Thus, the domain of the one-to-one function is the range of its inverse function and vice versa. Therefore, the range of the inverse is: $[4, \infty)$.