Trigonometric Functions and Reference Angles

This video tutorial introduces reference triangles and angles, explaining how they are used to find trigonometric expressions for special angles like 30, 45, and 60 degrees. It covers the concept of reference angles and their application in different quadrants to determine the sign and value of trigonometric functions. The tutorial also demonstrates how to use these concepts to find trig values for angles beyond 90 degrees.

What is a reference triangle primarily used for?

• To calculate the area of a triangle

• To find trigonometric expressions based on special angles

• To determine the length of a hypotenuse

• To measure angles in a circle

Which angles are considered special in the context of reference triangles?

• 60, 90, 120

• 30, 45, 60

• 45, 60, 90

• 15, 30, 45

In the first reference triangle, what is the length of the hypotenuse?

• Root 2

• Root 3

• 1

• 2

How is sine 30 degrees calculated using the reference triangle?

• Opposite over hypotenuse

• Hypotenuse over opposite

• Adjacent over hypotenuse

• Opposite over adjacent

What is the value of sine 30 degrees?

• 1

• Root 2/2

• 1/2

• Root 3/2

For cos 30 degrees, what is the adjacent side length in the reference triangle?

• Root 2

• 1

• Root 3

• 2

What is the value of tan 30 degrees?

• 1/2

• 1

• Root 2/2

• Root 3/3

In the reference triangle for 45 degrees, what is the length of each leg?

• 2

• Root 2

• Root 3

• 1

What is the value of sine 45 degrees?

• 1

• Root 3/2

• Root 2/2

• 1/2

How is tan 45 degrees calculated?

• Opposite over hypotenuse

• Hypotenuse over opposite

• Opposite over adjacent

• Adjacent over hypotenuse