Consider the figures:
Side square l e diagonal 
Side equilateral triangle I and height 
Sine, cosine and 30º tangent
Applying the definitions of sine, cosine and tangent to the 30º angles, we have:
Sine, cosine and 45 ° tangent
Applying the definitions of sine, cosine and tangent to an angle of 45º, we have:
Sine, cosine and 60 ° tangent
Applying the definitions of sine, cosine and tangent to an angle of 60º, we have:
summing up:
| x | sen x | waistband x | tg x |
| 30º |  |  |  |
| 45º |  | |  |
| 60º | | |  |
