# 3: Functions by Formulas and Graphs

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• 3.1: Functions given by formulas
Most of the time we will discuss functions that take some real numbers as inputs, and give real numbers as outputs. These functions are commonly described with a formula.
• 3.2: Functions given by graphs
In many situations, a function is represented by its graph. The graph of a function f is the set of all points (on the coordinate plane) of the form (x,f(x)) , where x is in the domain of f .
• 3.3: Exercises

This page titled 3: Functions by Formulas and Graphs is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Thomas Tradler and Holly Carley (New York City College of Technology at CUNY Academic Works) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.