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Introduction to radians
Learn about radians, which are the official unit of measurement for angles in algebra (in contrast to degrees, which are used in geometry).
Sal explains the definition and motivation for radians and the relationship between radians and degrees.
Sal discusses the general approach to converting between radians and degrees and vice versa.
Sal converts the degree measures 150° and -45° to radians.
Sal converts the radian measures π and -π/3 to degrees.
Convert angle measures given in degrees to radians and vice versa.
Sal determines the quadrant at which a ray falls after a rotation by a certain measure of radians.