To determine the sign of \(\sin\left(\frac{5\pi}{4}\right)\) and the quadrant in which it lies, let's analyze the angle \(\frac{5\pi}{4}\).
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Convert to degrees: \[ \frac{5\pi}{4} \times \frac{180^\circ}{\pi} = \frac{5 \times 180^\circ}{4} = 225^\circ \] This angle is in standard position.
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Identify the quadrant: An angle of \(225^\circ\) lies in Quadrant III, where both sine and cosine are negative.
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Determine the sign of \(\sin\) in this quadrant: Since \(\frac{5\pi}{4}\) is located in Quadrant III, the sine function is negative in this quadrant.
Based on this analysis, the correct response is:
sin(5π4) is negative and lies in Quadrant III.