Values of the trigonometric ratios
For triangle ABC:
\begin{align}\text{sin} \ \theta &= \dfrac{5}{13}\\ \text{cos} \ \theta &= \dfrac{12}{13}\\ \text{tan} \ \theta &= \dfrac{5}{12}\end{align}Using a calculator
Given any angle \(\theta\), the values of sin \(\theta\), cos \(\theta\) and tan \(\theta\) can be found using a calculator:
sin 30° = 0.5
cos 30° ≈ 0.8660 (correct to 4 decimal places)
tan 30° ≈ 0.5774 (correct to 4 decimal places)
Because the hypotenuse is the longest side of the triangle, the sine and cosine ratios are always less than 1.
0 < sin \(\theta\) < 1 and 0 < cos \(\theta\) < 1


