## What Does Domain Mean in Algebra?

### Domain

A function is a set of inputs that assign outputs to independent variables. For example, f(x) has the domain of all positive real numbers and the range of all negative real numbers. The codomain is similar, except that it contains every possible output that a function can produce. Finding the domain of a function with equation form is easy, but you need to remember a few things. First, if there is a denominator in the formula, exclude values that force it to be zero. Second, if there is an even root in the formula, exclude any real numbers that result in a negative number in the radicand. If you can, write the answer in interval form.

### Using interval notation

Interval notation is a method of describing a set of values that involves identifying the intervals to be included and writing the intervals in order from smallest to largest. You can use this method for describing a graph or table. Figure 3.2.4 compares inequality notation, set-builder notation, and interval notation.

Defining the domain and range of a function is important because it helps you determine which values are assigned to an independent variable. For instance, if you want to find out how far Bob drove on his summer job, you need to know the domain and range of his car’s fuel consumption.

In algebra, the domain of a function is the set of inputs that a function assigns to independent variables. For example, if a function f(x) assigns inputs such as India, Pakistan, Australia, Sri Lanka to its outputs the amount of money you earn per hour, then the domain of f(x) is the set of all inputs y that are greater than or equal to 6.

If you need to find the range of a function, you can use a range graph. To do this, draw a line from the far left point to the nearest point on the graph. Then, continue tracing the graph until you reach the next point on the line.

Understanding the range of a function is important because it can help you understand how much the outputs change when you make changes to the inputs. For example, if you want to determine how many miles Bob drove on his summer job, you need a graph that shows he traveled about 30 miles on one gallon of gas.

In algebra, the domain and range of a function is often determined by the way the function is written in equation form. The most common method of finding the domain of a function is to look at its formula and identify any restrictions on the input. For example, if you have a function with a denominator in its formula, you should look for values that force the denominator to be zero. Similarly, if you have a function with an even root in its formula, you should look for values in the domain that force the radicand to be negative.