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Question
Prove that:
\[\frac{sin\theta \cos(90° - \theta)cos\theta}{\sin(90° - \theta)} + \frac{cos\theta \sin(90° - \theta)sin\theta}{\cos(90° - \theta)}\]
Solution
\[\begin{array}{l} LHS = \frac{\cos( {90}^\circ - \theta)\sec( {90}^\circ - \theta)\tan\theta}{\text{cosec} ( {90}^\circ- \theta)\sin( {90}^\circ - \theta)\cot( {90}^\circ - \theta)} + \frac{\tan( {90}^\circ - \theta)}{\cot\theta} \\ \end{array}\]
\[\begin{array}{l}= \frac{\sin\theta \text cosec\theta\tan\theta}{\sec\theta\cos\theta\tan\theta} + \frac{\cot\theta}{\cot\theta} \\ \end{array}\]
= 1 + 1
= 2
= RHS
Hence proved.
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