Question 252901
Here is the original question:
{{{((1/a^2) - (1/b^2) ) * ( 2ab / (a-b))}}}
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step 1 subtract the fractions in the first (_). We get
{{{(b^2-a^2)/(a^2b^2)}}}
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step 2: factor the numerator to (a+b)(a-b). We get
{{{( a+b)(a-b)/a^2b^2}}}  * {{{( 2ab / (a-b))}}}
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step 3: cancel like terms from any top and any bottom. Looks like this when done:
{{{(a+b)/ab * 2/1}}} = 2(a+b)/ab