Find the reference angle for each angle.
-25π/6

Key Concepts

Reference Angle

The reference angle is the acute angle formed by the terminal side of a given angle and the x-axis. It is always measured as a positive angle and is used to simplify the calculation of trigonometric functions. For angles in standard position, the reference angle can be found by subtracting or adding multiples of π/2 or π, depending on the quadrant in which the angle lies.

Angle Measurement

Angles can be measured in degrees or radians, with radians being the standard unit in trigonometry. To convert between the two, one radian is approximately 57.3 degrees. Understanding how to work with angles in radians is crucial, especially when dealing with angles greater than 2π or less than 0, as is the case with negative angles.

Coterminal Angles

Coterminal angles are angles that share the same terminal side but differ by a full rotation, which is 2π radians (or 360 degrees). To find a coterminal angle, you can add or subtract 2π from the given angle. This concept is particularly useful when working with angles that are outside the standard range of 0 to 2π, as it allows for simplification when finding reference angles.