How do you find the supplement of a radian measure?

1 Answer
May 2, 2015

Two angles are, by definition, supplementary if their sum measured in degrees is 180^o. Measured in radians, their sum should be equal to pi because 180^o = pi radians.

So, if your angle is given in radians, subtract it from pi to get a supplementary angle in radians.

Example:
Angle alpha is measured in radians as pi/3 (it's 60^o, by the way).

It's supplementary angle is
pi - pi/3 = (2pi)/3 (which is 120^o)