How to evaluate the difference of two angles for cosine function

The video tutorial explains the use of the cosine difference formula, focusing on evaluating trigonometric functions for specific angles. It covers the understanding of coordinate points on the unit circle and the process of simplifying trigonometric expressions. The tutorial emphasizes the importance of simplification for achieving full credit in exams.

What is the cosine difference formula used in trigonometry?

• cos(U - V) = sin(U)cos(V) - cos(U)sin(V)

• cos(U - V) = cos(U)cos(V) + sin(U)sin(V)

• cos(U - V) = cos(U)cos(V) - sin(U)sin(V)

• cos(U - V) = sin(U)sin(V) + cos(U)cos(V)

What is the coordinate point for the angle 9π/4 on the unit circle?

• (1/2, sqrt 3 / 2)

• (-1/2, -sqrt 3 / 2)

• (-sqrt 3 / 2, 1/2)

• (sqrt 2 / 2, sqrt 2 / 2)

Which value represents the sine of 5π/6?

• sqrt 2 / 2

• 1/2

• -sqrt 3 / 2

• -1/2

What is the simplified form of the expression sqrt 2 * 1 - sqrt 6 / 4?

• -sqrt 3 + 1

• sqrt 3 - 1

• -sqrt 6 + sqrt 2

• sqrt 6 - sqrt 2

What common factor is used to simplify the expression involving sqrt 6 and sqrt 2?

• sqrt 3

• 2

• 4

• sqrt 2