How do you find the domain of f(x) = (x+2)/(x-3) f(x)=x+2x3?

1 Answer
Jun 7, 2016

Domain = {x:xepsilon RR, x != 3}

This reads as "The domain is the set of all elements x, such that x is an element of the set of Real numbers, but x is not equal to 3"

Explanation:

The domain is the set of all the possible x-values.

Looking at the numerator, any x-value can be used.

However, in a fraction the denominator may not be equal to 0.

In this case is x = 3, then the denominator will be 0, so x may not be 3, but any other value would be fine. We write it as:

Domain = {x:xepsilon RR, x != 3}

This reads as "The domain is the set of all elements x, such that x is an element of the set of Real numbers, but x is not equal to 3"