Evaluate cosine of an angle using the difference of two angles formula

The video tutorial explains how to rewrite angles as sums or differences, focusing on cosine. It covers reducing angles, labeling them as U and V, and applying the cosine difference formula. The instructor emphasizes the importance of evaluating trigonometric values accurately and demonstrates simplifying and factoring results. The tutorial also highlights the need to be cautious when switching between radians and degrees.

What is the equivalent expression for cosine of four π / 12 minus three π / 12?

• Cosine of π / 6

• Cosine of π / 12

• Cosine of π / 3

• Cosine of π / 4

When using the cosine difference formula, what should you label the angles as?

• U and V

• A and B

• X and Y

• M and N

Which formula is used for the difference of cosine?

• Cosine of U times Cosine of V minus Sine of U times Sine of V

• Sine of U times Sine of V minus Cosine of U times Cosine of V

• Cosine of U times Cosine of V plus Sine of U times Sine of V

• Sine of U times Cosine of V plus Cosine of U times Sine of V

What is the cosine of π / 3?

• sqrt 2 / 2

• sqrt 3 / 2

• 1/2

• 1

How can the expression sqrt 2 / 4 + sqrt 6 / 4 be simplified?

• sqrt 2 + sqrt 6

• sqrt 2 / 2 + sqrt 6 / 2

• 1/4 (sqrt 2 + sqrt 6)

• 1/2 (sqrt 2 + sqrt 6)