OpenStax, Algebra and Trigonometry 2e §9.4 Sum-to-Product and Product-to-Sum Formulas · Example 3 · Trigonometry · Compound & multiple angles

Express the Product as a Sum or Difference

Write $cos (3 θ) cos (5 θ)$ as a sum or difference.

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OpenStax, Algebra and Trigonometry 2e · §9.4 Sum-to-Product and Product-to-Sum Formulas · Example 3

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