OpenStax, Algebra and Trigonometry 2e §9.2 Sum and Difference Identities · Example 1 · Trigonometry · Compound & multiple angles

Finding the Exact Value Using the Formula for the Cosine of the Difference of Two Angles

Using the formula for the cosine of the difference of two angles, find the exact value of $cos (\frac{5 π}{4} - \frac{π}{6}) .$

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OpenStax, Algebra and Trigonometry 2e · §9.2 Sum and Difference Identities · Example 1

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