There is one more way to combine sets which will be useful for us: the Cartesian product, \(A \times B\text{.}\) This sounds fancy but is nothing you haven't seen before. When you graph a function in calculus, you graph it in the Cartesian plane. This is the set of all ordered pairs of real numbers \((x,y)\text{.}\) We can do this for any pair of sets, not just the real numbers with themselves.
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