These are the three fundamental trigonometric ratios. For a right triangle with angle θ, they describe the relationship between the angle and the ratios of the triangle's sides:
A right triangle has a hypotenuse of 10 and opposite side of 6. Find the angle θ.
sin θ = O / H = 6 / 10 = 0.6θ = sin⁻¹(0.6)| Angle | sin | cos | tan |
|---|---|---|---|
| 0° | 0 | 1 | 0 |
| 30° | ½ | √3/2 | 1/√3 |
| 45° | √2/2 | √2/2 | 1 |
| 60° | √3/2 | ½ | √3 |
| 90° | 1 | 0 | undefined |