OpenStax, Algebra and Trigonometry 2e §9.5 Solving Trigonometric Equations · Exercise 188 · Trigonometry · Identities

Solving Trigonometric Equations · Exercise 188

Prove the identity.

Two frequencies of sound are played on an instrument governed by the equation $n (t) = 8 cos (20 π t) cos (1000 π t) .$ What are the period and frequency of the “fast” and “slow” oscillations? What is the amplitude?

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OpenStax, Algebra and Trigonometry 2e · §9.5 Solving Trigonometric Equations · Exercise 188

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