# How do the Special Right Triangles relate to the Unit Circle?

Each black-and-red (or black-and-yellow) triangles is a special right-angled triangle. The figures outside the circle - $\frac{\pi}{6} , \frac{\pi}{4} , \frac{\pi}{3}$ - are the angles that the triangles make with the horizontal (x) axis. The other figures - $\frac{1}{2} , \frac{\sqrt{2}}{2} , \frac{\sqrt{3}}{2}$ - are the distances along the axes - and the answers to $\sin \left(x\right)$ (yellow) and $\cos \left(x\right)$ (red) for each angle.