help in cos/tan/csc

cos(-pi/6) csc(-pi/3) tan(-pi/6) = ?

$\begin{array}{rcll} \cos( \frac{-\pi}{6} )\cdot \csc( \frac{-\pi}{3} ) \cdot\tan( \frac{-\pi}{6} ) &&\\\\ =\cos( \frac{-\pi}{6} )\cdot \frac{1}{\sin( \frac{-\pi}{3} )}\cdot \tan( \frac{-\pi}{6} )\\\\ \boxed{~ \cos( \frac{-\pi}{6} ) = +\cos( \frac{\pi}{6} ) = \frac{1}{2}\sqrt{3} \\ \sin( \frac{-\pi}{3} ) = -\sin( \frac{\pi}{3} ) = -\frac{1}{2}\sqrt{3} \\ \tan( \frac{-\pi}{6} ) = -\tan( \frac{\pi}{6} ) = -\frac{1}{3}\sqrt{3} ~}\\\\ =( \frac{1}{2}\sqrt{3} ) \cdot \left( \frac{1}{-\frac{ 1 }{2}\sqrt{3}} \right)\cdot (-\frac{1}{3}\sqrt{3})\\\\ =\left( \frac{ \frac{1}{2}\sqrt{3} }{-\frac{ 1 }{2}\sqrt{3}} \right)\cdot (-\frac{1}{3}\sqrt{3})\\\\ =( -1 )\cdot (-\frac{1}{3}\sqrt{3})\\\\ =\frac{1}{3}\sqrt{3}\\\\ \mathbf{\cos( \frac{-\pi}{6} )\cdot \csc( \frac{-\pi}{3} ) \cdot\tan( \frac{-\pi}{6} ) =\frac{1}{3}\sqrt{3}} \end{array}$