The domain of the function as you wrote it is all real numbers except 0. However, I think you probably meant to write
In that case, the domain is all real numbers except the two zeros of the polynomial in the denominator. In other words, solve:
to find the two values to exclude from the domain.
If this is the case, you should have used parentheses to include the -64 in the denominator. That is x/(x^2 - 64) inside of the curly braces would have rendered like this:
John
My calculator said it, I believe it, that settles it