Learn how to verify an identity by using the sum and difference formulas

The video tutorial explains the cosine addition formula, starting with identifying the components needed for the formula. It then applies the formula using specific values, referencing the unit circle to explain cosine values. The lesson concludes with simplifying the expression and summarizing the key points.

What is the addition formula for cosine as mentioned in the text?

Explain the significance of the unit circle in relation to cosine of X.

What is the X value at the point corresponding to three π / 2 on the unit circle?

How does the sine of three π / 2 relate to the sine of X?

What happens to any value multiplied by zero according to the text?