Answer
$(-2,3)$
Work Step by Step
The function remains constant in an interval when, moving from left to right, the y-values continue to remain constant for all x-values in that interval. For the graph in the question, the y-values remain constant for all values of $x$ between $-2$ and $3$. Since the ends of the interval are represented by open circles, both $-2$ and $3$ are not included in the interval. As a result, parentheses will be used on both sides.
Therefore, the function remains constant in the interval $(-2,3)$.