Use the Pythagorean identity from a sine value
An acute angle \(\theta\) has \(\sin\theta=\frac{8}{17}\). Use the identity \(\sin^{2}\theta+\cos^{2}\theta=1\) to find \(\sin^{2}\theta\), \(\cos^{2}\theta\), and \(\cos\theta\).
Worked practice: trigonometric identity
Square the sine value, subtract from one, then take the positive cosine value.
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