Domain and Range of a Function

This applet demonstrates how to find the domain and range of a function from its graph and express them using interval notation. Through dynamic visual representation, the tool helps users intuitively understand the possible values that the independent variable (x-values) and dependent variable (y-values) can take, reinforcing the fundamental connection between graphical analysis and interval notation. Students can interactively explore various functions and observe how the horizontal extent of the graph corresponds to the domain while the vertical extent corresponds to the range. The applet shows how to identify whether endpoints are included or excluded, translating this directly into correct bracket and parenthesis usage in interval notation. By manipulating the graph or observing pre-loaded examples, learners develop a deeper conceptual understanding of what domain and range represent beyond rote memorization. This makes it an excellent auxiliary tool for mastering foundational function concepts and image analysis, suitable for students at the introductory algebra and precalculus levels.