Evaluating trigonometric functions using the reference angle

The video tutorial explains how to find the cosine of 300 degrees using both traditional graphing methods and reference angles. Initially, the process involves graphing the angle on the unit circle and identifying corresponding coordinates. The tutorial then introduces reference angles as a more efficient method, explaining how to calculate the reference angle and use it to find the cosine value. The cosine of 300 degrees is shown to be equal to the cosine of its reference angle, 60 degrees, simplifying the process.

What is the first step in finding the cosine of 300 degrees using the unit circle method?

• Memorize the cosine values

• Use a calculator

• Graph the angle

• Calculate the reference angle

In which quadrant is the angle 300 degrees located?

• Third quadrant

• Second quadrant

• First quadrant

• Fourth quadrant

How do you calculate the reference angle for an angle in the fourth quadrant?

• Subtract the angle from 360 degrees

• Divide the angle by 2

• Subtract the angle from 180 degrees

• Add 90 degrees to the angle

What is the reference angle for 300 degrees?

• 30 degrees

• 45 degrees

• 60 degrees

• 90 degrees

Why are reference angles useful in trigonometry?

• They simplify the calculation of sine values

• They are only used for angles in the first quadrant

• They provide exact values for all angles

• They eliminate the need for graphing