Unit-circle values

What this lesson shows

Four compass points on the unit circle: 0, 90, 180 and 270 degrees. Their sine and cosine you shouldn't have to compute — you should SEE them.

Try it yourself

Real questions from this lesson's worksheets — answers below each one.

1. Drag the point around the circle so the angle θ = 30°.
   Show answer

   30
2. Right triangle: opposite = 3, adjacent = 4. Find tan θ
   Show answer

   3/4
3. Evaluate sin 30°.
   Show answer

   1/2
4. Evaluate sin 0°.
   Show answer

   0