# Introduction to radians

5 videos

1 skill

Learn about radians, which are the official unit of measurement for angles in algebra (in contrast to degrees, which are used in geometry).

### Intro to radians

VIDEO
10:51 minutes

Sal explains the definition and motivation for radians and the relationship between radians and degrees.

### Radians & degrees

VIDEO
7:12 minutes

Sal discusses the general approach to converting between radians and degrees and vice versa.

### Radians & degrees

PRACTICE PROBLEMS

Convert angle measures given in degrees to radians and vice versa.

### Radian angles & quadrants

VIDEO
3:51 minutes

Sal determines the quadrant at which a ray falls after a rotation by a certain measure of radians.