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Question
Prove that:
\[cot\theta \tan\left( 90° - \theta \right) - \sec\left( 90° - \theta \right)cosec\theta + \sqrt{3}\tan12° \tan60° \tan78° = 2\]
Solution
\[ = \frac{1 + 1}{3 \times \tan27°\times \frac{1}{\tan27°}}\]
\[ = \frac{2}{3}\]
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