The Unit Circle

Front

What is the unit circle?

Back

The unit circle is a circle with a radius of 1 unit centered at the origin (0,0) in the coordinate plane.

Front

What are the coordinates of the point on the unit circle at 0°?

Back

(1, 0)

Front

What are the coordinates of the point on the unit circle at 90°?

Back

(0, 1)

Front

What are the coordinates of the point on the unit circle at 180°?

Back

(-1, 0)

Front

What are the coordinates of the point on the unit circle at 270°?

Back

(0, -1)

Front

In which quadrants is cosθ positive?

Back

In the 1st and 4th quadrants.

Front

In which quadrants is sinθ positive?

Back

In the 1st and 2nd quadrants.

Front

What is the reference angle for 150°?

Back

30°

Front

What is the reference angle for -30°?

Back

30°

Front

What is the cosine of 150°?

Back

-√3/2