Nilai fungsi trigonometri sudut $45\degree$

$$\begin{align*} \sin(45\degree) &= \dfrac{\sqrt{2}}{2} \\ \cos(45\degree) &= \dfrac{\sqrt{2}}{2} \\ \tan(45\degree) &= 1 \end{align*}$$

Nilai fungsi trigonometri sudut $30\degree$ dan $60\degree$

$$\begin{align*} \sin(30 \degree) &= \dfrac{1}{2} \\ \cos(30 \degree) &= \dfrac{\sqrt{3}}{2} \\ \tan(30 \degree) &= \dfrac{\sqrt{3}}{3} \\ \sin(60 \degree) &= \dfrac{\sqrt{3}}{2} \\ \cos(60 \degree) &= \dfrac{1}{2} \\ \tan(60 \degree) &= \sqrt{3} \end{align*}$$

Nilai fungsi trigonometri sudut $15\degree$

$$\begin{aligned} \sin(15\degree) &= \frac{\sqrt{2}}{4}(\sqrt{3} - 1) \\ \cos( 15\degree ) &=\frac{\sqrt{2}}{4}\left(\sqrt{3} +1\right) \\ \tan( 15\degree ) &=2-\sqrt{3} \end{aligned}$$

Nilai fungsi trigonometri sudut $15\degree$

$$\begin{align*} \sin(18\degree) &=\frac{\sqrt{5}-1}{4}\\ \cos(18\degree) &=\frac{\sqrt{10+2\sqrt{5}}}{4}\\ \tan(18\degree) &=\sqrt{\frac{5-2\sqrt{5}}{5}}\\ \sin(72\degree) &=\frac{\sqrt{10+2\sqrt{5}}}{4}\\ \cos(72\degree) &=\frac{\sqrt{5}-1}{4}\\ \tan(72\degree) &=\sqrt{5+2\sqrt{5}} \end{align*}$$