Simplifying an expression using the sum of two angles for cosine

The video tutorial addresses the challenge of transitioning from numbers to variables in mathematical expressions. It emphasizes the importance of applying known processes to new problems, specifically focusing on simplifying expressions using the cosine of a sum formula. The instructor guides students through labeling variables, substituting values, and evaluating expressions using the unit circle. The tutorial concludes with a setup for a problem, reinforcing the learned concepts.

What is the main challenge when variables are introduced into mathematical expressions?

• They require a different process than numbers.

• They are not applicable in trigonometry.

• They can confuse the application of known processes.

• They make the expressions unsolvable.

What is the first step in simplifying a trigonometric expression involving variables?

• Ignore the variables and focus on constants.

• Convert all variables to numbers.

• Label the variables and identify the operation.

• Evaluate the expression directly.

In the cosine addition formula, what operation is performed between the cosine and sine terms?

• Multiplication

• Subtraction

• Addition

• Division

What is the coordinate point for π on the unit circle?

• (0, 1)

• (1, 0)

• (0, -1)

• (-1, 0)

What happens to the term involving sine of Theta when simplifying the expression?

• It becomes negative.

• It becomes zero.

• It doubles in value.

• It remains unchanged.