OpenStax, Algebra and Trigonometry 2e §9.5 Solving Trigonometric Equations · Example 14 · Trigonometry · Identities

Use Identities to Solve an Equation

Use identities to solve exactly the trigonometric equation over the interval $0 \leq x < 2 π .$

$cos x cos (2 x) + s in x s in (2 x) = \frac{3}{2}$

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OpenStax, Algebra and Trigonometry 2e · §9.5 Solving Trigonometric Equations · Example 14

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