Question 721092
simplify this problem: 
(x^2-y^2)/(x+y)/(x^4-y^4)
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= (x-y)/(x^4-y^4)
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= (x-y)/[(x^2+y^2)(x+y)(x-y)]
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= 1/[(x^2+y^2)(x+y)]
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Cheers,
Stan H.
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