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OpenStax, Algebra and Trigonometry 2e §9.5 Solving Trigonometric Equations · Review Exercise 140 · Trigonometry · Identities

Solving Trigonometric Equations · Review Exercise 140

Evaluate the sum by using a product formula. Write the exact answer.

$cos (\frac{5 π}{12}) + cos (\frac{7 π}{12})$

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OpenStax, Algebra and Trigonometry 2e · §9.5 Solving Trigonometric Equations · Review Exercise 140

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