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 the point at an angle of 0 radians on the unit circle?

Back

(1, 0)

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(π/2)?

Back

1

Front

What is the value of cos(π)?

Back

-1

Front

What is the value of sin(3π/2)?

Back

-1

Front

What is the value of cos(3π/2)?

Back

0

Front

What are the coordinates of the point at an angle of π/4 on the unit circle?

Back

(√2/2, √2/2)

Front

What are the coordinates of the point at an angle of 5π/4 on the unit circle?

Back

(-√2/2, -√2/2)