Chapter 9 - Section 9.2 - Composite and Inverse Functions - Exercise Set - Page 687: 45

Does not have an inverse function.

The Horizontal line test says that if a function can be intersected by a horizontal line more than once, it doesn't have an inverse. Otherwise, it has an inverse A horizontal line will intersect the graph in more than $1$ point. Thus by the Horizontal line test, the graph does not have an inverse function.