We are given the following function

We are asked to find the domain of this function.
Domain:
The domain is all the possible values of input (x) for which the function is defined.
For the given case, notice that when x = 3, the denominator becomes 0 and hence the function is undefined.
So, the possible values of x are from negative infinity to less than 3 and greater than 3 to positive infinity (excluding 3)
Therefore, the domain of the function is
