Question

A function is a relationship between two quantities, called the ___ and the ____.

Short answer

The two quantities in a function are called the 'domain' and the 'range'.

Step-by-step solution

Identifying the first set

The first set of a function is called the 'domain'. The domain is the set of all possible inputs (also known as 'independent values') that the function can accept.

Identifying the second set

The second set of a function is called the 'range'. The range is the set of all possible outputs (also known as 'dependent values') that the function can produce.

Key concepts

Domain of a Function

In algebra, the domain of a function is a fundamental concept used to define the set of all possible inputs for the function. It includes all the independent values that you can substitute into the function equation without encountering any mathematical errors or undefined operations such as division by zero.

For example, if you have a function defined by the equation \( f(x) = \frac{1}{x} \), the domain would be all real numbers except zero, since dividing by zero is undefined. Understanding the domain is crucial when graphing functions or solving equations, as it informs us about the range of values that make sense within the context of a specific problem.

Range of a Function

Complementing the domain, the range of a function refers to the set of all possible outputs that the function can produce. After determining the domain and substituting each input value, the resulting outputs form the range. For instance, if you square any real number, the result is always at least zero or positive. Therefore, the range of the function \( g(x) = x^2 \) is all real numbers greater than or equal to zero.

Understanding the range helps us anticipate the potential results of a function and provides insight into the function's behavior across its entire domain.

Independent Values in Functions

When dealing with functions, independent values are those that you can freely choose from the domain. Think of them as the inputs or 'x' values in an equation. They are called independent because their selection is not influenced by the function or other variables; rather, the function's output depends on them.

For any function \( f(x) \), 'x' represents an independent variable, and altering 'x' will change the function's outcome or 'y' value. Thus, a clear understanding of independent values is necessary to control and anticipate changes in the dependent values, which are the outputs of the function.

Dependent Values in Functions

In contrast to independent values, dependent values are determined by the function once the independent values are chosen. These are the outputs or 'y' values that depend on the inputs. If you imagine a function as a machine, after you put in an independent value (input), the machine processes it according to the function's rule, and then it gives back a dependent value (output).

For every input in the domain, there is a corresponding output in the range of the function. Recognizing dependent values is essential in understanding the cause-and-effect relationship inherent in functions, where each input has a direct impact on the output.