Reference Angles and Trigonometric Functions

The video tutorial explains how to evaluate the sine, cosine, and tangent of 840 degrees using co-terminal and reference angles. It covers the process of finding reference angles, understanding co-terminal angles, and determining coordinate points on the unit circle. The tutorial emphasizes the importance of knowing the first quadrant of the unit circle and the rules for different quadrants.

What is the main goal of the video tutorial?

• To understand the history of trigonometry

• To evaluate trigonometric functions for 840 degrees

• To learn how to draw a unit circle

• To memorize the unit circle

What is the first step in evaluating trigonometric functions for 840 degrees?

• Finding the reference angle

• Drawing a triangle

• Finding the terminal side on the unit circle

• Calculating the sine value

In which direction do we move to find the terminal side of 840 degrees?

• Positive direction

• Counterclockwise direction

• Negative direction

• Clockwise direction

What is the reference angle for 840 degrees?

• 30 degrees

• 45 degrees

• 60 degrees

• 90 degrees

Why can't we use angles greater than 360 degrees when finding reference angles?

• They are not co-terminal

• They are not on the unit circle

• They are not acute angles

• They are too large to calculate

What is the smallest co-terminal angle for 840 degrees?

• 300 degrees

• 240 degrees

• 180 degrees

• 120 degrees

Which formula is used to verify the reference angle in the third quadrant?

• Theta Prime = Theta - 180

• Theta Prime = Theta + 90

• Theta Prime = Theta - 90

• Theta Prime = Theta + 180

What is the reference angle for 240 degrees?

• 30 degrees

• 45 degrees

• 60 degrees

• 90 degrees

Why is it important to know the unit circle?

• To calculate angles quickly

• To understand trigonometric functions

• To draw perfect circles

• To memorize all angles

What are the coordinates for 60 degrees on the unit circle?

• (1, 0)

• (0, 1)

• (√3/2, 1/2)

• (1/2, √3/2)