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Ch. 6 - Inverse Circular Functions and Trigonometric Equations
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161, 9780135440780, 9780136881117, 9780135440827, 9780135924891Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 41

Solve each equation for exact solutions.
arccos x + 2 arcsin √3/2 = π

Guida verificata passo dopo passo
1
Recognize that the equation is \(\arccos x + 2 \arcsin \frac{\sqrt{3}}{2} = \pi\). Our goal is to solve for \(x\).
Evaluate the known inverse trigonometric value: find \(\arcsin \frac{\sqrt{3}}{2}\). Recall that \(\sin \frac{\pi}{3} = \frac{\sqrt{3}}{2}\), so \(\arcsin \frac{\sqrt{3}}{2} = \frac{\pi}{3}\).
Substitute this value back into the equation: \(\arccos x + 2 \times \frac{\pi}{3} = \pi\), which simplifies to \(\arccos x + \frac{2\pi}{3} = \pi\).
Isolate \(\arccos x\) by subtracting \(\frac{2\pi}{3}\) from both sides: \(\arccos x = \pi - \frac{2\pi}{3} = \frac{\pi}{3}\).
Use the definition of \(\arccos\) to solve for \(x\): since \(\arccos x = \frac{\pi}{3}\), then \(x = \cos \frac{\pi}{3}\). Recall that \(\cos \frac{\pi}{3} = \frac{1}{2}\).

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