You can
put this solution on YOUR website!1/x + 1/y/ 1/y - 1/x
= 1/y/1/y
= 1
Note: This question makes better sense as (1/x + 1/y)/(1/y - 1/x). Without the parenthesis, the answer would be 1;
Had there been a parenthesis,
(1/x + 1/y)/(1/y - 1/x)
= [(x+y)/xy][xy/(x-y)]
= (x+y)/(x-y)