Understanding Set Cardinality

The video tutorial explains how to determine the cardinality of the union and intersection of two sets, A and B, given their individual cardinalities. It introduces the formula for calculating the cardinality of a union and demonstrates its application through three cases: when sets are disjoint, when one is a subset of the other, and when they are not disjoint. The tutorial verifies the formula's correctness in each scenario, ensuring a comprehensive understanding of set operations.

What is the cardinality of set A?

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What is the cardinality of set B?

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What is the formula for the cardinality of A union B?

• Cardinality of A intersect B

• Cardinality of A plus cardinality of B

• Cardinality of A plus cardinality of B minus cardinality of A intersect B

• Cardinality of A minus cardinality of B

In the formula, what do you add to both sides to find the sum of the cardinalities of A union B and A intersect B?

• Cardinality of A intersect B

• Cardinality of A

• Cardinality of A union B

• Cardinality of B

When A and B are disjoint, what is the cardinality of A intersect B?

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In Case 1, what is the cardinality of A union B when A and B are disjoint?

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When B is a subset of A, what is the cardinality of A union B?

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In Case 2, what is the cardinality of A intersect B when B is a subset of A?

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In Case 3, if there are 3 elements in the intersection of A and B, how many elements are only in A?

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In Case 3, what is the total cardinality of A union B?

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