Function

Definition

A function is a mathematical relationship between two or more variables, where one variable (the dependent variable) depends on the value of the other variable(s) (the independent variable(s)). Functions describe how one quantity changes in relation to another, and they are widely used in various fields, including mathematics, science, and engineering.

5 Must Know Facts For Your Next Test

1. Functions can be represented in various forms, including equations, graphs, tables, and verbal descriptions.
2. The domain of a function is the set of all possible input values, and the range is the set of all possible output values.
3. Function notation, such as $f(x)$, is used to represent the relationship between the independent and dependent variables.
4. Transformations, such as shifts, reflections, and stretches, can be applied to functions to create new functions with different properties.
5. Modeling using variation, such as direct variation and inverse variation, involves the use of functions to describe relationships between variables.

Review Questions

• Explain the relationship between the domain and range of a function.
  • The domain of a function is the set of all possible input values, while the range is the set of all possible output values. The domain and range are closely related because the domain determines the possible inputs, which in turn determine the possible outputs, or the range. Understanding the domain and range of a function is crucial for analyzing its behavior and properties, as well as for solving problems involving functions.
• Describe how function notation, such as $f(x)$, is used to represent the relationship between variables.
  • Function notation, like $f(x)$, is a way of representing the relationship between the independent and dependent variables. The function name, $f$, represents the relationship, and the variable in parentheses, $x$, represents the independent variable. The value of $f(x)$ is the dependent variable, which depends on the value of the independent variable, $x$. This notation allows for a concise and clear representation of the functional relationship, which is essential for understanding and working with functions in various mathematical and scientific contexts.
• Explain how the concept of functions is used in the context of modeling using variation, such as direct and inverse variation.
  • Functions are fundamental to modeling using variation, as they allow us to describe the relationship between two or more variables. In the case of direct variation, the relationship between the variables can be expressed as a linear function, where one variable is proportional to the other. Inverse variation, on the other hand, involves a hyperbolic function, where one variable is inversely proportional to the other. Understanding the properties of these types of functions and how to use them to model real-world situations is crucial for solving problems involving variation and for making predictions based on the relationships between the variables.

Related terms

Domain:

The domain of a function is the set of all possible input values for which the function is defined.

Range:

The range of a function is the set of all possible output values that the function can produce.

Function Notation:

Function notation is a way of representing a function, where the function name is followed by the independent variable(s) in parentheses, such as $f(x)$ or $g(x,y)$.