and if you plug the numbers into the equation, and you get some number over zero, then the limit doesn't exist at that point. If you get zero over some number, the limit is zero.
>>x at 1 would not be in the domain of f(x )?
Well, it is. It doesn't have a limit at that point, and it isn't a function if at x = 1 the function has two values. This is akin to the fact that if you graph a circle using polar coordinates it is a relation but not a function because for certain values of x you have two values of y. You can graph a semi circle and have it be a function, but not a full circle and have it be a function.
