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3-129.

​Below are two of the special angles that are used in the unit circle. Identify the radian measure for each angle shown. Remember, counterclockwise angles are positive and clockwise angles are negative. 

  1. Unit circle, with horizontal & vertical diameters, curved arrow starts from positive, x axis, going counter clockwise to the negative, y axis.

    A full circle is an angle of radians. What is 3/4s of that?

  1. Unit circle, with horizontal & vertical diameters, curved spiral arrow starts from positive, x axis, going clockwise all the way around & through the positive x axis, continuing around to a radius in the middle of first quadrant.

    Divide the circle into eight equal pieces. Then remember that four of those pieces are equivalent to radians.