How it works
This unit circle quiz lights one blank box and you pick what goes in it: the angle in degrees, the angle in radians, or the point (cos θ, sin θ). The three 0° boxes are filled in as the example.
Read the full guide
Degrees, then radians, then points
Each ring of boxes is asked in two rounds. Degrees sit inside the circle, radians just outside it, and the points on the outer ring. Every round reaches round the whole circle: the axes, 30°, 45° and 60°, and the other three quadrants. A wrong pick writes the right value in the box.
A blank unit circle printable
After a round you can print the unit circle worksheet blank, with numbered boxes and lines to fill in, or labeled as a cheat sheet with all 48 values.
- Learn the first quadrant only. Every other point is the same pair with one or both signs flipped.
Questions and answers
How do I get from degrees to radians?
Multiply by π/180: 30° is π/6, 45° is π/4, 120° is 2π/3 and 180° is π. For a unit circle radians quiz, choose Radians under Start from.
Why is the point (cos θ, sin θ)?
The circle has radius 1, so the point where the angle's side meets it is x = cos θ and y = sin θ. At 30° that is (√3/2, 1/2), and at 60° the two numbers swap places.
Where does tan fit on the unit circle?
Tan θ is sin θ divided by cos θ, the y of the point over its x. At 45° both are √2/2, so tan 45° = 1. At 90° and 270° x is 0, so tan is undefined.