You can put this solution on YOUR website! Sketch -2π/3 in standard position and find its reference angle in degrees and radians.
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(-2/3)pi = -120 degrees
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The reference angle is the positive angle between -120 and the
nearest portion or the x-axis.
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Reference angle = 60 degrees
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Reference angle = 60(pi/180) = pi/3 radians
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Cheers,
Stan H.