Question

determine the domain on which the following function is increasing.

Explanation:

Step1: Recall the concept of increasing function

A function \(y = f(x)\) is increasing on an interval if for any two points \(x_1\) and \(x_2\) in the interval with \(x_1eq0\)), if \(a<0\) (opens down - like the given graph), it is increasing to the left of the vertex.

Step2: Analyze the graph

From the graph (a parabola opening down), we observe the direction of increase. The function is increasing from the left - hand side up to the vertex.

Answer:

\((-\infty, 4)\)