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Exact Values of Trigonometric Ratios for 30°, 45°, and 60°


The special right triangles can be used to determine the exact values of the trigonometric ratios for angles of \(30^\circ\), \(45^\circ\), and \(60^\circ\).

The exact values of sin \(\theta\), cos \(\theta\), and tan \(\theta\) for an angle \(\theta\), where \(\theta\) is \(30^\circ\), \(45^\circ\), and \(60^\circ\), are summarized in the table.

\(\theta\) sin \(\theta\) cos \(\theta\) tan \(\theta\)
\[30^\circ\] \[\frac{1}{2}\] \[\frac{\sqrt{3}}{2}\] \[\frac{\sqrt{3}}{3}\]
\[45^\circ\] \[\frac{\sqrt{2}}{2}\] \[\frac{\sqrt{2}}{2}\] \[1\]
\[60^\circ\] \[\frac{\sqrt{3}}{2}\] \[\frac{1}{2}\] \[\sqrt{3}\]