## Precalculus (6th Edition) Blitzer

$[0, 3)$;domain
The shaded x-values are from 0 to 3. A hole was used at $x=3$, therefore 3 is not included in the set. Thus, the interval notation that represents the shaded set of numbers is $[0, 3)$. The set of x-values of a function is called its domain.