1. The problem statement, all variables and given/known data 2. Relevant equations a^2-b^2 = (a+b)(a-b) a^2-2ab+b^2 = (a-b)(a-b) a^2+2ab+b^2 = (a+b)(a+b) 3. The attempt at a solution SOLVED IT! Look at the bottom! With my first try i got the answer 0 The result of first parenthesis was 1 /(√x+√y) From there on it went like this 1 /(√x+√y) - 1 /(√x+√y) = 0 I'm suspecting that i might have messed up the order of operations, but not sure. I did the calculation inside the paranthesis first, then reversed it (^-1) The answer should come like this (2√y)/(x-y) Solution: Should be more careful next time.. i made an error when writing it down for myself. :) Now, with the correct signs i got 1 /(√x-√y) from the first paranthesis, and from there on it was all piece of cake. Thanks.