Principal values of the trigonometric functions between 0 ° and 90 ° are:
| sine | cosine | tangent | |
| 0 ° | 0 | 1 | 0 |
| 30 ° | \[\frac{1}{2}\] |
\[\frac{\sqrt{3}}{2}\] |
\[\frac{1}{\sqrt{3}}\] |
| 45 ° | \[\frac{1}{\sqrt{2}}\] |
\[\frac{1}{\sqrt{2}}\] |
1 |
| 60 ° | \[\frac{\sqrt{3}}{2}\] |
\[\frac{1}{2}\] |
\[\sqrt{3}\] |
| 90 ° | 1 | 0 | Not Defined |
Suppose we want to find the exact value of 12cos30°-2tan60°. We consult the table.
\[12cos30°-2tan60°=12 \times \frac{\sqrt{3}}{2} - 2 \times \sqrt{3} = 6 \sqrt{3}-2 \sqrt{3}=4 \sqrt{3}\]