Common Core · High school
HSF-TF.A.3
High school — Use special triangles to find sine, cosine and tangent for π/3, π/4 and π/6, and use the unit circle for π − x, π + x and 2π − x.
A note on this mapping: HSF-TF.A.3 is a (+) standard — Common Core marks it as beyond the college- and career-ready threshold, i.e. precalculus rather than Algebra II.
The skill that covers it
What a student should be able to do
- Give exact sine and cosine for the special angles.
- Use reference angles and quadrant signs.
- Relate coordinates on the unit circle to (cos t, sin t).
- Evaluate trig functions of angles beyond one full turn.