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Question
Prove that: \[\frac{\sin 2x}{1 - \cos 2x} = cot x\]
Solution
\[LHS = \frac{\sin2x}{1 - \cos2x}\]
\[ = \frac{2 sin x \times cos x}{2 \sin^2 x} \left( \because \sin2x , 1 - \cos2x = 2 \sin^2 x \right) \]
`= (2 sin x xx cos x)/(2 sin x xx sin x) `
`= (cos x)/(sin x) `
` = cot x = RHS`
\[\text{ Hence proved } .\]
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