Свойства тригонометрических функций
| \(\alpha\) | 0 | \(30^0\) | \(45^0\) | \(60^0\) | \(90^0\) | \(180^0\) | \(270^0\) | \(360^0\) |
| 0 | \(\displaystyle\frac{\pi}{6}\) | \(\displaystyle\frac{\pi}{4}\) | \(\displaystyle\frac{\pi}{3}\) | \(\displaystyle\frac{\pi}{2}\) | \(\pi\) | \(\displaystyle\frac{3\pi}{2}\) | \(2\pi\) | |
| \(\sin\alpha\) | 0 | \(\displaystyle\frac{1}{2}\) | \(\displaystyle\frac{\sqrt{2}}{2}\) | \(\displaystyle\frac{\sqrt{3}}{2}\) | 1 | 0 | -1 | 0 |
| \(\cos\alpha\) | 1 | \(\displaystyle\frac{\sqrt{3}}{2}\) | \(\displaystyle\frac{\sqrt{2}}{2}\) | \(\displaystyle\frac{1}{2}\) | 0 | -1 | 0 | 1 |
| tg \(\alpha\) | 0 | \(\displaystyle\frac{\sqrt{3}}{3}\) | 1 | \(\sqrt{3}\) | \(\infty\) | 0 | \(\infty\) | 0 |
| ctg \(\alpha\) | \(\infty\) | \(\sqrt{3}\) | 1 | \(\displaystyle\frac{\sqrt{3}}{3}\) | 0 | \(\infty\) | 0 | \(\infty\) |
\(\sin(-\alpha)=-\sin\alpha\)
\(\cos(-\alpha)=\cos\alpha\)
\(\mathrm{tg}(-\alpha)=-\mathrm{tg}\alpha\)
\(\mathrm{ctg}(-\alpha)=-\mathrm{ctg}\alpha\)