Evaluate cosine using the sum and difference formula

The video tutorial covers the application of the cosine addition formula, specifically for angles 60 and 45 degrees. The instructor emphasizes that while the addition will be provided during tests, students should be prepared to handle it independently in homework and future assessments. The tutorial includes a step-by-step evaluation of the cosine and sine values for these angles, highlighting common mistakes and the importance of careful calculation.

What is the formula used for calculating the cosine of the sum of two angles?

Explain the significance of the unit circle in evaluating trigonometric functions.

What mistakes do students commonly make when calculating trigonometric functions?

How do you evaluate cosine of 60 degrees and cosine of 45 degrees?

What are the sine values for 60 degrees and 45 degrees?