Understanding Intervals of a Function

The video tutorial explains how to interpret a function graph by identifying intervals where the function is either above or below the x-axis. It begins with an introduction to plotting functions on a graph, followed by exercises to highlight intervals where the function is negative (below the x-axis) and positive (above the x-axis). The tutorial emphasizes understanding the relationship between the function's value and its position relative to the x-axis.

What does it mean for a function f(x) to be less than 0?

• The graph is above the x-axis.

• The graph is on the x-axis.

• The graph is below the x-axis.

• The graph is on the y-axis.

In which interval is the function f(x) negative?

• Where the graph is below the x-axis.

• Where the graph is above the x-axis.

• Where the graph is on the y-axis.

• Where the graph is on the x-axis.

What indicates that a function f(x) is greater than 0?

• The graph is below the x-axis.

• The graph is on the y-axis.

• The graph is on the x-axis.

• The graph is above the x-axis.

Which area shows that f(x) is positive?

• Where the graph is above the x-axis.

• Where the graph is on the x-axis.

• Where the graph is below the x-axis.

• Where the graph is on the y-axis.

How can you identify an interval where f(x) is greater than 0?

• By finding where the graph is on the y-axis.

• By finding where the graph is above the x-axis.

• By finding where the graph is on the x-axis.

• By finding where the graph is below the x-axis.

What happens to the graph of f(x) when it is positive?

• It stays on the y-axis.

• It goes below the x-axis.

• It stays on the x-axis.

• It goes above the x-axis.

Where does the function f(x) go when it is greater than 0?

• On the y-axis.

• Below the x-axis.

• On the x-axis.

• Above the x-axis.