Problem 12 of 7
Use the Pythagorean identity to find sine when cos(theta)=9/41 and theta is in Quadrant IV.
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solve sin^2(theta)=1-cos^2(theta).
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Cosine value must be in [-1,1] and quadrant must determine sine sign.
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Solution
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1. Use sin^2(theta)=1-cos^2(theta).
2. Take the square root of the remaining value.
3. Choose the sign of sine from the quadrant.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Giving both positive and negative values when quadrant is specified.