Understanding the Vertical Line Test

The video tutorial reviews the vertical line test, a method to determine if a relation is a function. It explains that a relation is a function if every input has exactly one output. A graph is a function if no vertical line intersects it more than once. The tutorial includes examples of graphs, showing how vertical lines can be used to test if they are functions. It concludes with a summary of the key points.

What is the main criterion for a relation to be considered a function?

• Every input has multiple outputs.

• Every output has exactly one input.

• Every output has multiple inputs.

• Every input has exactly one output.

What does the vertical line test determine about a graph?

• If a graph is symmetrical.

• If a graph is a function.

• If a graph is linear.

• If a graph is continuous.

In the first graph, why is it considered a function?

• Because it has multiple curves.

• Because it is a straight line.

• Because it is a closed shape.

• Because no vertical line intersects it more than once.

Why is the second graph not a function?

• Because it is a parabola.

• Because it is a circle.

• Because it is a horizontal line.

• Because vertical lines intersect it more than once.

What characteristic of the third graph makes it not a function?

• It is a single point.

• Each vertical line intersects it more than once.

• It is a closed loop.

• It is a straight line.

Why is the fourth graph considered a function?

• Because it is a vertical line.

• Because it is a diagonal line.

• Because it is a horizontal line.

• Because no vertical line intersects it more than once.