Coterminal & Reference Angles

Front

What is a coterminal angle?

Back

Coterminal angles are angles that share the same terminal side when drawn in standard position. They can be found by adding or subtracting multiples of 360 degrees (or 2π radians).

Front

How do you find a reference angle for an angle in quadrant 1?

Back

For angles in quadrant 1, the reference angle is the angle itself.

Front

What is the formula for finding the reference angle in quadrant 2?

Back

Reference angle = 180 degrees - Actual angle.

Front

What is the formula for finding the reference angle in quadrant 3?

Back

Reference angle = Actual angle - 180 degrees.

Front

What is the formula for finding the reference angle in quadrant 4?

Back

Reference angle = 360 degrees - Actual angle.

Front

How do you convert a negative angle to a positive angle?

Back

To convert a negative angle to a positive angle, add 360 degrees (or 2π radians) until the angle is positive.

Front

What is the reference angle for -300 degrees?

Back

The reference angle for -300 degrees is 60 degrees.

Front

What is the reference angle for 240 degrees?

Back

The reference angle for 240 degrees is 60 degrees.

Front

What is the sine of 120 degrees?

Back

The sine of 120 degrees is √3/2.

Front

How do you determine the quadrant of an angle?

Back

The quadrant of an angle can be determined by its degree measure: 0-90° (Quadrant I), 90-180° (Quadrant II), 180-270° (Quadrant III), 270-360° (Quadrant IV).