Don't multiply the numerator. Leave it like the product of the two factors and notice that the denominator can be factored as (x-1)(x+1)
Never multiply out the numerator in this type of problem. If you leave it as (x-1)(sqrt(...)+2) and simplify x\^2 +3 -4 as x\^2 - 1, you should be able to factor that to be able to cancel out the problematic x-1 factor in the top.
Factor the denominator and don't expand the numerator. You will see something you can cancel.

HINT: Always look for a factor that includes your limit. Meaning: if your limit is x->1 look to factor out (x-1) from the denominator.
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