Set the denominator equal to zero. Remember, dividing by 0 is undefined. So if we find values of x that make the denominator zero, then we must exclude them from the domain.
Since makes the denominator equal to zero, this means we must exclude from our domain
So our domain is:
which in plain English reads: x is the set of all real numbers except
So our domain looks like this in interval notation
note: remember, the parenthesis excludes 0 from the domain
If we wanted to graph the domain on a number line, we would get:
Graph of the domain in blue and the excluded value represented by open circle
Notice we have a continuous line until we get to the hole at (which is represented by the open circle).
This graphically represents our domain in which x can be any number except x cannot equal 0
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