Problem 153 of 7
Use Pythagorean identity with known value cos theta=sqrt(2)/2 in Quadrant IV.
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apply sin^2+cos^2=1.
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Apply sin^2+cos^2=1 for missing coordinate values.
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Solution
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1. Substitute the known sine or cosine into sin^2+cos^2=1.
2. Solve for the missing magnitude.
3. Use quadrant information to choose the sign.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Positive-only square root when quadrant requires negative value.