Special Trigonometric Values

Below are the key degree-radian conversions and special sine, cosine, and tangent values that all trigonometry students should know.

$$\begin{array}{ccccc}\text{degrees}& \text{radians}& \text{sin}& \text{cos}& \text{tan}\\ 0^{\circ }& 0& 0& 1& 0\\ 30^{\circ }& \frac{\pi }{6}& \frac{1}{2}& \frac{\sqrt{3}}{2}& \frac{\sqrt{3}}{3}\\ 45^{\circ }& \frac{\pi }{4}& \frac{\sqrt{2}}{2}& \frac{\sqrt{2}}{2}& 1\\ 60^{\circ }& \frac{\pi }{3}& \frac{\sqrt{3}}{2}& \frac{1}{2}& \sqrt{3}\\ 90^{\circ }& \frac{\pi }{2}& 1& 0& \text{undef.}\end{array}$$

These values come from the standard values on the unit circle in Quadrant I. The full unit circle is shown below.

To practice these values until you know them by heart, try my Unit Circle Quiz.