Glossary Checklist FAQ

Functions are often represented as equations. Function notation identifies the independent variable in the equation. The independent variable is always placed on the \(x\)-axis and is considered the input value. The output value is called the dependent variable and is always placed on the \(y\)-axis.

The equation of the function \(f(x) = 7x \) is expressed in function notation. This function can be read as “\(f \) of \(x \) equals \(7\) times \(x \)” or simply “\(f \) of \(x \) equals \(7x \)”.

Using this notation, \(x \) represents the input and \(f(x) \) represents the output. The function notation \(f(x) \) is read “\(f \) of \(x \)” and does not mean \(f \thinspace {\color{red}{\times}} \thinspace x \). \(f(x) \) is a single variable and can be treated like \(y \).