Evaluate a trigonometric value using period as an aide - Online Math Teacher

The video tutorial explains how to evaluate the cosine of angles greater than 2π by simplifying them using the unit circle. It demonstrates breaking down angles into thirds and highlights the redundancy of 2π in calculations. The tutorial walks through calculating the cosine of 2π/3, emphasizing the reflection about the Y-axis and the resulting negative value. The key takeaway is understanding how to factor out 2π to simplify angle evaluations.

What is the purpose of breaking down angles into thirds when evaluating cosine?

• To simplify the calculation by ignoring full revolutions

• To make the angle larger

• To change the angle to radians

• To convert the angle to degrees

How can you simplify an angle greater than 2π when evaluating cosine?

• By adding 2π to the angle

• By multiplying the angle by 2

• By factoring out 2π and focusing on the remainder

• By converting the angle to degrees

What is the significance of the remainder when simplifying angles?

• It is added to 2π

• It is used to convert the angle to degrees

• It determines the new angle to evaluate

• It is ignored in the calculation

How is the cosine value determined for angles reflected across the Y-axis?

• By adding 1 to the cosine value

• By using the Y-coordinate

• By doubling the cosine value

• By taking the negative of the X-coordinate

What happens to the cosine value when an angle is reflected across the Y-axis?

• It becomes positive

• It remains the same

• It becomes negative

• It doubles