Question 829440
 tan^2x-cot^2x/tanx+cotx=tanx-cot x
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Cross-multiply to get:
tan^2(x)-cot^2(x) = (tan(x)+cot(x))(tan(x)-cot(x))
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Then tan^2(x)-cot^2(x) = tan^2(x)-cot^2(x) 
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Cheers,
Stan H.
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