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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 13

Solve each equation for x, where x is restricted to the given interval.
y = ― 2 cos 5x , for x in [0, π/5]

Guida verificata passo dopo passo
1
Identify the given equation: \(y = -2 \cos 5x\) and the interval for \(x\) is \([0, \frac{\pi}{5}]\).
Since the problem asks to solve for \(x\), determine the value of \(y\) you want to solve for. If a specific \(y\) value is given, set \(-2 \cos 5x = y\); if not, clarify the target \(y\) value or condition.
Isolate the cosine term by dividing both sides by \(-2\): \(\cos 5x = -\frac{y}{2}\).
Use the inverse cosine function to solve for \$5x$: \(5x = \arccos\left(-\frac{y}{2}\right)\) and consider the general solutions for cosine within the interval.
Divide the solutions for \$5x$ by 5 to find $x$, then check which solutions lie within the interval \([0, \frac{\pi}{5}]\).

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