# HSF-TF.C.9

Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

## Tasks

Sum and Difference angle formulas

Coordinates of equilateral triangles

Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

Sum and Difference angle formulas

Coordinates of equilateral triangles