College Math

College Math Study Guide

There are some rules to remember about the union of sets. 1. The union of a set with an empty set gives the set A, that is A ∪ ø = A 2. The union of a set with the same set is equal to the set itself, that is A ∪ A = A 3. The union of two sets is equal to the reverse of the union of two sets, that is A ∪ B = B ∪ A 4. The union of three sets in different combinations would also be same, that is (A ∪ B) ∪ C = A ∪ (B ∪ C) Intersection of Sets: Suppose we are given two sets, A and B, then the intersection of the two sets would be such that the resultant subset would have all the elements which are present in both Set A and Set B. It is denoted by the symbol ∩. For instance, we are given the following sets: A = {2, 4, 6, 8} and B = {1, 2, 3, 4, 5} Then A ∩ B = {2, 4} We can represent the sets and their operations using Venn diagrams. The intersection of two sets is given by the Venn diagram as shown below:

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