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?

~8 minWritten answer · compare with the solution

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

Stuck? A gentle nudge

No hints for this one.

Something off?

Workspace

Your working

Check your full solution

Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.