Unit Circle

Front

What is the definition of a unit circle?

Back

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

Front

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

Back

(1, 0)

Front

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

Back

(0, 1)

Front

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

Back

(-1, 0)

Front

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

Back

(0, -1)

Front

What is the sine of an angle in the unit circle?

Back

The sine of an angle is the y-coordinate of the point on the unit circle corresponding to that angle.

Front

What is the cosine of an angle in the unit circle?

Back

The cosine of an angle is the x-coordinate of the point on the unit circle corresponding to that angle.

Front

What is the value of sin 30°?

Back

1/2

Front

What is the value of cos 60°?

Back

1/2

Front

What is the value of sin 45°?

Back

√2/2