Find the domain:

Question

 f(x) = 1/x+7 + 3/x-9?

Answer 1

The function

We know that all possible values of x  is domain of a function.

A rational function is simply fraction and in a fraction the denominator cannot be equal to 0 because it would be undefined.

To find, which number make the fraction undefined create an equation where the denominator is not equal to zero.

So, the domain of the function is all real numbers except -7 and 9.

Domain set is .