MINI LESSON

Intervals of Increase and Decrease

A parabola changes direction at its vertex.

To the left of the vertex, a parabola may be increasing or decreasing.

To the right of the vertex, the behavior reverses.

An interval of increase describes where the function values get larger as \(x\) increases.

Question 1

A parabola is graphed on the set of axes below. Over which interval is the parabola only increasing?