How to evaluate for cos without using a calculator or the unit circle

The video tutorial explains how to evaluate trigonometric functions using reference angles. It covers the concept of coterminal angles, how to determine the quadrant of an angle, and the significance of reference angles in trigonometry. The tutorial emphasizes the importance of understanding the quadrant to determine the sign of trigonometric values and provides a practical example using the cosine function.

What is the purpose of using a reference angle when evaluating trigonometric functions?

• To increase the angle's value

• To convert the angle to degrees

• To change the angle to a different quadrant

• To simplify calculations by using a known angle

How can coterminal angles be found?

• By adding or subtracting 2π

• By multiplying the angle by 2π

• By dividing the angle by 2

• By converting the angle to degrees

What is the significance of determining the quadrant of an angle?

• To convert the angle to radians

• To determine the sign of the trigonometric function

• To simplify the angle to a smaller value

• To find the angle's exact value

In which quadrant is the angle 11π/6 located?

• First Quadrant

• Second Quadrant

• Third Quadrant

• Fourth Quadrant

What is the reference angle for 11π/6?

• π/2

• π/6

• π/4

• π/3

When evaluating cosine in the fourth quadrant, what is the sign of the result?

• Undefined

• Zero

• Positive

• Negative

What is the cosine of π/6 equivalent to in degrees?

• 45 degrees

• 60 degrees

• 30 degrees

• 90 degrees