Evaluate using the Unit Circle

Front

What is the Unit Circle?

Back

The Unit Circle is a circle with a radius of 1 centered at the origin (0,0) in the coordinate plane. It is used to define trigonometric functions for all angles.

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 tangent of an angle in the Unit Circle?

Back

The tangent of an angle is the ratio of the sine to the cosine of that angle, or tan(θ) = sin(θ)/cos(θ).

Front

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

Back

(1, 0)

Front

What are the coordinates of the point at π/2 radians on the Unit Circle?

Back

(0, 1)

Front

What are the coordinates of the point at π radians on the Unit Circle?

Back

(-1, 0)

Front

What are the coordinates of the point at 3π/2 radians on the Unit Circle?

Back

(0, -1)

Front

What is the value of sin(π/6)?

Back

1/2

Front

What is the value of cos(π/3)?

Back

1/2