The reference angle is the smallest angle between the terminal side and the x-axis.
300 degrees is in the 4th quadrant.
So, the reference angle is
Hence, the reference angle of 300 degrees is 60 degrees
225 degrees is in the 3rd quadrant.
So, the reference angle is
Hence, the reference angle of 225 degrees is 45 degrees
480 degrees is in the 2nd quadrant (i.e. 480 - 360 = 120)
So, the reference angle is
Hence, the reference angle of 480 degrees is 60 degrees
-210 degrees is in the 2nd quadrant (i.e. 360 - 210 = 150)
So, the reference angle is
Hence, the reference angle of -210 degrees is 30 degrees
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