Union Formula:
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The union of two sets represents all distinct elements that belong to either set, while the intersection represents elements common to both sets. The fundamental relationship between these concepts is expressed by the inclusion-exclusion principle.
The calculator uses the inclusion-exclusion principle:
Where:
Explanation: This formula accounts for the fact that elements in both sets are counted twice if we simply add A and B, so we subtract the intersection once to get the correct count.
Details: Understanding set relationships is fundamental in probability, statistics, database theory, and many areas of mathematics and computer science. Accurate calculations help in determining probabilities, analyzing data relationships, and solving combinatorial problems.
Tips: Enter the sizes of both sets and their intersection. All values must be non-negative integers. The intersection cannot exceed the size of either set.
Q1: What if my intersection is larger than one of the sets?
A: This is mathematically impossible. The intersection can never be larger than either of the individual sets.
Q2: What does a zero intersection mean?
A: A zero intersection means the sets are disjoint - they have no elements in common. The union is simply the sum of both set sizes.
Q3: Can I use this for more than two sets?
A: This calculator is for two sets only. For more sets, the inclusion-exclusion principle becomes more complex.
Q4: What's the maximum union size possible?
A: The maximum union is A + B (when intersection = 0), and the minimum is max(A, B) (when one set is completely contained in the other).
Q5: How is this related to probability?
A: In probability, this principle helps calculate the probability of either event A or B occurring: P(A∪B) = P(A) + P(B) - P(A∩B).