Radians & the Unit Circle REVIEW

Front

Back

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.

Front

Find the reference angle for -15°.

Back

15°

Front

What is the measure of the angle -940 degrees?

Back

-940 degrees is coterminal with 140 degrees.

Front

Back

Front

What are the negative and positive coterminal angles of -225°?

Back

135°, -585°.

Front

What is the unit circle?

Back

The unit circle is a circle with a radius of 1 centered at the origin of the coordinate plane.

Front

What is the cosine of 0 radians?

Back

1

Front

What is the sine of 90 degrees?

Back

1

Front

How do you find coterminal angles?

Back

Add or subtract multiples of 360° (or 2π radians) to the given angle.