# What is the range of #f(x) = 3x + 4#?

##### 1 Answer

**and** range for that functions is all real numbers. In fact, the domain and range for any linear function is all real numbers.

So, in interval notation:

The domain (or possible input(

The range (or possible output(

*Note the round brackets ( ) used.Since infinity isn't a number, the function isn't exactly "defined" there, it just keeps tending to infinity. If the function was defined on a certain interval, we would put [square brackets] around it

When you're trying to figure out a domain, you can think about if the function is continuous. Is there any place where the function is **not** defined, so you're not allowed to plug into a value (like a 0 in the denominator)? Are there any places where there are asymptotes?

In the case of linear functions like