The intersection of two sets are all the elements that appear in both sets. For example, if you have the two sets of numbers: {3,4,5,6,7}, and {5,6,7,8,9,10}, the intersection of these sets is:{5,6,7}. The symbol for intersection is an upside-down capital U, so if we call our first set "A" and our second set "B" then the set {5,6,7} is
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