Unit Circle Trigonometry

Front

What is the definition of 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.

Front

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

Back

(1, 0)

Front

What is the value of sin(θ) on the unit circle?

Back

The value of sin(θ) is the y-coordinate of the point on the unit circle corresponding to the angle θ.

Front

What is the value of cos(θ) on the unit circle?

Back

The value of cos(θ) is the x-coordinate of the point on the unit circle corresponding to the angle θ.

Front

What is the relationship between sine and cosecant?

Back

Cosecant is the reciprocal of sine: csc(θ) = 1/sin(θ).

Front

What is the value of csc(π)?

Back

Undefined, because sin(π) = 0.

Front

What is the value of csc(9π/4)?

Back

√2, because sin(9π/4) = 1/√2.

Front

What are the values of sin and cos at 90 degrees (π/2 radians)?

Back

sin(π/2) = 1 and cos(π/2) = 0.

Front

What is the value of cos(0)?

Back

1.

Front

What is the value of sin(0)?

Back

0.