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OpenStax, Algebra and Trigonometry 2e §9.5 Solving Trigonometric Equations · Exercise 191 · Trigonometry · Identities

Solving Trigonometric Equations · Exercise 191

Prove the identity.

Water levels near a glacier currently average 9 feet, varying seasonally by 2 inches above and below the average and reaching their highest point in January. Due to global warming, the glacier has begun melting faster than normal. Every year, the water levels rise by a steady 3 inches. Find a function modeling the depth of the water months from now. If the docks are 2 feet above current water levels, at what point will the water first rise above the docks?

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OpenStax, Algebra and Trigonometry 2e · §9.5 Solving Trigonometric Equations · Exercise 191

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