Ask Dr. Math

Domain and Range of a Function

Domain and Range of a Function, a selection of answers from the Dr. Math archives.

Domain and Range

Can you please explain about domain and range?

Domain and Range of Functions

I am learning in school about the domain and range of functions. Why are they called domain and range? And where did they come from?

Finding the Domain of a Function

How do you find the domain of this function: f(x) = (4+x)/(x^2-9)?

Finding The Domain and Range of a Function

How do I find the domain and range of a function? My problem is f(x) = x squared -2.

How to Find the Range of a Function

How do you find the range of a function like g(x) = (x+1)/(x^2-1)?

Domain, Range, and Asymptote

How do you find the domain, range, and asymptote of a function?

Range

If f(x) = x-3/x+3, I know the domain to be all Reals except for -3. The range, however, is all Reals except for 1. I don't know how they get the 1 algebraically.

Range and Domain of a Graph

Determine the domain and range of the graph of "f" that starts at (- 2,3), goes down to (0,0), and ends at (3,4).

Range of a Function

Describe the range of the function g(x) = e^(-2x).

Natural Domain of a Function

Some inputs don't make sense for some functions.

Functions: Domain, Range, and Piecewise

What are piecewise functions? What are open and closed points? How do you figure out the domain and range of a function without graphing it on a calculator?

Domain and Range of x^x

What is the domain and range of x^x?

Domain and Range of an Inverse Function

Why is the domain of a function equal to the range of the inverse function?

Domain, Asymptotes, Intercepts of a Function

What is the domain of this function? What asymptotes does it have? What are the x and y intercepts? Etc...

Domain of a Composite Function

I don't completely understand how to find the domain of a composite function. Could you please explain it?