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TopNewestExpand to get \(1+\cot A +\cot B +\cot A \cot B\).Then use the formula for \(\cot (A+B)\) to find a relation \(1+\cot A +\cot B=\cot A \cot B\) – Akshay Bodhare · 2 years, 3 months ago

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Please prove this – Ashley Shamidha · 2 years, 3 months ago

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