# 4.1: Function Notation

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The notation for a function is generally the $$f(x)$$ notation. In learning about graphing in algebra we typically use the $$x$$ and $$y$$ notation, that is: $$y=6 x-1$$ In function notation, the dependent variable $$y$$ is replaced by the notation $$f(x):$$
$f(x)=6 x-1$
Function values for particular values of the independent variable $$x$$ can be found
by substituting the appropriate $$x$$ value into the formula.
$\begin{array}{c} f(9)=6(9)-1=53 \\ f(9)=53 \end{array}$

Find each of the following values for the given functions:
$$f(0) \quad f(-1) \quad f(3) \quad f\left(\frac{1}{2}\right) \quad f(x+2) \quad f(x+h)$$
1) $$\quad f(x)=2 x^{2}-3 x+1$$
2) $$\quad f(x)=5 x^{2}+x-7$$
3) $$\quad f(x)=\frac{x}{x^{2}-1}$$
4) $$\quad f(x)=\frac{x+3}{x^{2}+1}$$

This page titled 4.1: Function Notation is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Richard W. Beveridge.