From the following picture:
we can find the values for the trigonometric functions for values as 30 and 60 degrees.
For instance, tan 30 is equal to
![\tan 30=\frac{1}{\sqrt[]{3}}](https://img.qammunity.org/2023/formulas/mathematics/college/p10w454aupj5ph9v78lbnqol0u62pj4inu.png)
Since
![\frac{1}{\sqrt[]{3}}=\frac{\sqrt[]{3}}{3}](https://img.qammunity.org/2023/formulas/mathematics/college/folkjbke5p95kn4a3nq5ucuqb2t7bd8e1y.png)
then,
![\tan 30=\frac{\sqrt[]{3}}{3}](https://img.qammunity.org/2023/formulas/mathematics/college/qeawovtf3a44ete614g0bfe7lk2blwdx17.png)
However, we have a minus sign, this imply the angle is negative. In other words,
![\tan -30=-\frac{\sqrt[]{3}}{3}](https://img.qammunity.org/2023/formulas/mathematics/college/f97bguv42m5vdgytteaqbnfu3n5ocqdfjb.png)
Now, since -30 = 330, then we have
![\tan 330=-\frac{\sqrt[]{3}}{3}](https://img.qammunity.org/2023/formulas/mathematics/college/ugf6f0a09xr0j2y51ury4jv9yji2xyh6k0.png)
so the answer is
