I think this is what you want: (you can use 'show source' to see how to format):
This is not an equation, it is an expression. The question must be to rationalize the expression (get rid of as many roots as possible, in particular, from the denominator):
Multiply top and bottom by
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Simplify denominator:
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Notice that
Multiply out the numerator, using the above equivalence:
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Factor out a 3 from the numerator and cancel it with one of the 3's in the denominator
9=3*3 so now the denominator is just 3: ( 3*Numerator / 9 = Numerator / 3 )
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Expand the contents of the radical signs
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In many cases, this is considered rationalized, and it can be left in this form.
The only additional step I see that might be needed by your teacher would be to
break (A+B)/3 into A/3 + B/3 because it lowers the exponents under the radical sign:
Starting with
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