Question

determine the domain on which the following function is increasing.

Explanation:

Step1: Identify vertex of parabola

The parabola's vertex is at $x=-2$.

Step2: Analyze increasing interval

For a downward-opening parabola, the function increases as $x$ approaches the vertex from the left, so the interval is $(-\infty, -2)$.

Answer:

$(-\infty, -2)$