Question 1203468
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The expression is the sum of two rational expression.  To determine the domain, there is no need (i.e., it is a lot of unnecessary work) to combine the two rational expressions into one, as one of the other tutors did.  The restrictions on the domain, if there are any, come from the two separate rational expressions.<br>
Restrictions on the domain of a rational expression are determined by values of x that make the denominator equal to 0.<br>
In the first expression, the denominator "x^2+9" is always positive, so there are no restrictions on the domain because of it.<br>
In the second expression, the denominator "x" is obviously equal to 0 only at x=0.<br>
So the only restriction on the domain for the given expression is that x can't be 0.<br>
ANSWER: the expression is undefined for a single value of x<br>