<PRE><B>Question 409503</B>
What is the reference angle of 13pi/8?
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(13/8)pi
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Find the angle between it and the x-axis.
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(13/8)pi = pi+(5/8)pi
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This angle is (1/8)pi into the 4th Quadrant.
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The terminal side is (3/8)pi from the positive x-axis.
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The reference angle is (3/8)pi
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Cheers,
Stan H.
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