Question 873197
sin(2t)-cot(t) = -cot(t)cos(2t)
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2sin(t)cos(t) = [-cos(t)/sin(t)][cos^2(t)-sin^2(t)]
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2sin(t)cos(t) = [-cos(t)/sin(t)][1-sin^2(t)-sin^2(t)] 
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2sin(t)cos(t) - [cos(t)/sin(t)] = (-cos(t)/sin(t))(1-2sin^2(t))
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Multiply each term by sin(t) to get rid of the denominators::
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2sin^2(t)cos(t) - cos(t) = (-cos(t)(1-2sin^2(t))
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2sin^2(t)cos(t) - cos(t) = -cos(t) + 2sin^2(t)cos(t) 
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Cheers,
Stan H.
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