[tex] -6 \sqrt{3} ( - \frac{\pi}{3} ) \times \ \tan(\frac{3\pi}{4} ) [/tex]

[tex]tan( \frac{3 \pi }{4}) = \frac{sin(\frac{3 \pi }{4})}{cos(\frac{3 \pi }{4})} = \frac{sin(\frac{ \pi }{4})}{-cos(\frac{ \pi }{4})} = - \frac{ \frac{ \sqrt{2} }{2} }{ \frac{ \sqrt{2} }{2} } = -1[/tex]

[tex]-6 \sqrt{3} ( -\frac{\pi}{3} ) * (-1) = -2 \pi \sqrt{3} [/tex]