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Ch. 3 - Radian Measure and The Unit Circle
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 75

Find the exact values of s in the given interval that satisfy the given condition.


[0 , 2π) ; cos² s = 1/2

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1
Start with the given equation: \(\cos^{2} s = \frac{1}{2}\).
Take the square root of both sides to solve for \(\cos s\): \(\cos s = \pm \sqrt{\frac{1}{2}}\).
Simplify the square root: \(\cos s = \pm \frac{\sqrt{2}}{2}\).
Recall the unit circle values where \(\cos s = \pm \frac{\sqrt{2}}{2}\), which correspond to angles \(s = \frac{\pi}{4}, \frac{3\pi}{4}, \frac{5\pi}{4}, \frac{7\pi}{4}\) within the interval \([0, 2\pi)\).
List these values as the exact solutions for \(s\) in the given interval.

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주요 개념

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