# Cross Sections of Graphs of Functions of Two Variables

Cross Sections of Graphs of Functions of Two Variables

The graph of a function of two variables can be better understood by looking at slices, or cross sections, of the graph parallel to the or planes. Slicing is equivalent to holding (or ) constant at and looking at the graph of the resulting single-variable function (or , respectively). This Demonstration helps students connect the slice on the 3D graph of with the 2D graph of or in its own right.

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