Question

1/a-1/b
-------
a/b-b/a


please simplify

triple decker fraction

you will have a common denominator of ab for the top and a common denominator of ab for the bottom, so they will cancel

remember that to divide one fraction by another, you multiply the first by the reciprocal of the second

after that I see a difference of square at the bottom
I see an answer of -1/(a+b)

see if that is what you get