There are two special triangles. These triangles are special because their angles are used to often. , and .

From these two triangles we can come up with 6 important trig ratios that come up quite often.

**How did we get those numbers?**

A is simply a square cut along its diagonal. If each side of the square was 1, then we’d use the Pythagorean Theorem to calculate the diagonal .

A triangle is an equilateral triangle, with side lengths of , cut by an altitude (segment from one angle, perpendicular to the opposite side). Again, two sides of the right triangle are known, so we apply the Pythagorean Theorem.\\