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Important angles and related results of the trigonometric functions

The following table shows a selection of frequently used angles and the associated results of the trigonometric functions sine and cosine.

\[ \require{cancel} \]
\[ [\alpha]=rad \]\[ [\alpha]=° \]\[ \sin \alpha \]\[ \cos \alpha \]
\[ 0 \]\[ 0° \]\[ 0 \]\[ 1 \]
\[ \frac{\pi}{6} \]\[ 30° \]\[ \frac{1}{2} \]\[ \frac{\sqrt{3}}{2} \]
\[ \frac{\pi}{4} \]\[ 45° \]\[ \frac{1}{\sqrt{2}} \]\[ \frac{1}{\sqrt{2}} \]
\[ \frac{\pi}{3} \]\[ 60° \]\[ \frac{\sqrt{3}}{2} \]\[ \frac{1}{2} \]
\[ \frac{\pi}{2} \]\[ 90° \]\[ 1 \]\[ 0 \]
\[ \frac{2\pi}{3} \]\[ 120° \]\[ \frac{\sqrt{3}}{2} \]\[ -\frac{1}{2} \]
\[ \frac{3\pi}{4} \]\[ 135° \]\[ \frac{1}{\sqrt{2}} \]\[ -\frac{1}{\sqrt{2}} \]
\[ \frac{5\pi}{6} \]\[ 150° \]\[ \frac{1}{2} \]\[ -\frac{\sqrt{3}}{2} \]
\[ \pi \]\[ 180° \]\[ 0 \]\[ -1 \]

The shown values are typically used for simplified notation of mechanical equations. In addition, the table can be used for the conversion between ° and radiant.

Angle conversion from Degree (°) to Radiant

\[ \alpha_{Radiant} = \frac{\alpha_{Degree}}{180°} \cdot \pi \]

Angle conversion from Radiant to Degree (°)

\[ \alpha_{Degree} = \frac{\alpha_{Radiant}}{\pi} \cdot 180° \]