Trig Unit 2B Review 2025

Front

What is a coterminal angle?

Back

Coterminal angles are angles that share the same terminal side when drawn in standard position. To find a coterminal angle, you can add or subtract multiples of 360° (or 2π radians).

Front

Find a coterminal angle for 180°.

Back

180° + 360° = 540° (coterminal angle).

Front

What is a reference angle?

Back

A reference angle is the acute angle formed by the terminal side of an angle and the x-axis. It is always positive and less than 90°.

Front

Find the reference angle for 210°.

Back

Reference angle = 210° - 180° = 30°.

Front

Back

The value is undefined because sin(180°) = 0.

Front

Find a coterminal angle for -90°.

Back

-90° + 360° = 270° (coterminal angle).

Front

What is the reference angle for 300°?

Back

Reference angle = 360° - 300° = 60°.

Front

Back

The value is 1.

Front

Find a coterminal angle for 450°.

Back

450° - 360° = 90° (coterminal angle).

Front

Back

The value is -1.