The Unit Circle

Front

What is the Unit Circle?

Back

A circle with a radius of 1 centered at the origin (0,0) in the coordinate plane, used to define trigonometric functions.

Front

What are the coordinates of the point at 0° on the Unit Circle?

Back

(1, 0)

Front

What are the coordinates of the point at 90° on the Unit Circle?

Back

(0, 1)

Front

What are the coordinates of the point at 180° on the Unit Circle?

Back

(-1, 0)

Front

What are the coordinates of the point at 270° on the Unit Circle?

Back

(0, -1)

Front

What is sin θ in terms of the Unit Circle?

Back

The y-coordinate of the point on the Unit Circle corresponding to angle θ.

Front

What is cos θ in terms of the Unit Circle?

Back

The x-coordinate of the point on the Unit Circle corresponding to angle θ.

Front

What is tan θ in terms of the Unit Circle?

Back

The ratio of sin θ to cos θ, or y/x for the point on the Unit Circle.

Front

What is the value of sin 30°?

Back

½

Front

What is the value of cos 60°?

Back

½