Domain and range from a graph

The video tutorial explains the concepts of domain and range in functions. It begins by defining the domain as the set of all X values that make up a function and discusses how to determine the domain by considering the extent of the graph along the X-axis. The tutorial addresses discontinuities, such as holes, where X values are not defined. It then transitions to the range, defined as the set of all Y values, and explains how to identify the range by examining the graph's vertical extent. The video also covers set notation and the use of the union symbol to represent combined domains.

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