What are the sum and difference formulas for cosine

The video tutorial explains the cosine sum and difference formulas, which are used to evaluate angles that are not easily calculated using a calculator or unit circle. By breaking down a complex angle into two smaller angles, the exact trigonometric value can be determined. The tutorial covers the specific formulas for both the sum and difference of cosine, detailing the steps to calculate these values using smaller angles. The explanation includes the importance of following the correct formula to achieve accurate results.

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