Radians

MathsDirect

Measuring angles in degrees is convenient on most occasions. The important angles are all whole numbers and the angles are easy to visualise. In Pure maths however, the preferred measure of angle is the radian.

This is defined as the length of arc subtended by the angle, divide by the radius.

Although degrees will still be used in maths, on some occasions it is essential that radians are used

Differentiation & Integration will not work with degrees.

The relationship between degrees and radians is given by

For a complete circle,

Below are the basic calculations that can be made using radians.

Calculate the angle given the radius and arc length.

Calculate the arc length, given the angle and radius.

Calculate the radius, given the angle and arc length.

You can also do calculations involving area.

You can find area by calculating the fraction of the whole circle

Area of a whole circle

Area of a fraction of a circle.

Calculate the area, given the radius and angle.

Calculate the angle, given the area and the radius

Go to degree/radian conversion

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