Cosecant of 300 Degrees

Theorem

$\csc 300^\circ = \csc \dfrac {5 \pi} 3 = -\dfrac {2 \sqrt 3} 3$

where $\csc$ denotes cosecant.


Proof

\(\ds \csc 300^\circ\) \(=\) \(\ds \csc \left({360^\circ - 60^\circ}\right)\)
\(\ds \) \(=\) \(\ds -\csc 60^\circ\) Cosecant of Conjugate Angle
\(\ds \) \(=\) \(\ds -\frac {2 \sqrt 3} 3\) Cosecant of 60 Degrees

$\blacksquare$


Sources

  • 1968: Murray R. Spiegel: Mathematical Handbook of Formulas and Tables ... (previous) ... (next): $\S 5$: Trigonometric Functions: Exact Values for Trigonometric Functions of Various Angles