OpenStax, Algebra and Trigonometry 2e §9.4 Sum-to-Product and Product-to-Sum Formulas · Example 1 · Trigonometry · Compound & multiple angles

Writing the Product as a Sum Using the Product-to-Sum Formula for Cosine

Write the following product of cosines as a sum: $2 cos (\frac{7 x}{2}) cos \frac{3 x}{2} .$

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OpenStax, Algebra and Trigonometry 2e · §9.4 Sum-to-Product and Product-to-Sum Formulas · Example 1

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