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Evaluate: $\frac{3 \cos^2 30^\circ - 6 \cosec^2 30^\circ}{\tan^2 60^\circ}$
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$3\times(\frac{\sqrt{3}}{2})^2 - 6\times(2)^2$ (1/2 Mark)
$\frac{3 \times \frac{3}{4} - 6 \times 4}{(\sqrt{3})^2}$ (1/2 Mark)
= $\frac{\frac{9}{4} - 24}{3}$ (1/2 Mark)
= $\frac{\frac{9-96}{4}}{3} = \frac{-87}{12}$ or $-\frac{29}{4}$ (1/2 Mark)
$\frac{3 \times \frac{3}{4} - 6 \times 4}{(\sqrt{3})^2}$ (1/2 Mark)
= $\frac{\frac{9}{4} - 24}{3}$ (1/2 Mark)
= $\frac{\frac{9-96}{4}}{3} = \frac{-87}{12}$ or $-\frac{29}{4}$ (1/2 Mark)