Question 319745
[(5/b) - (5/a)] / [(1/b^2) - (1/a^2)]
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5a-5b /ab  / (a^2-b^2) /a^2b^2
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5(a-b)/ab * a^2b^2/(a^2-b^2)
5(a-b)*a^2b^2 / ab(a+b)(a-b)
5ab / (a+b)