# What is a Power Set? | Set Theory, Subsets, Cardinality | Summary and Q&A

406.1K views
October 17, 2017
by
Wrath of Math
What is a Power Set? | Set Theory, Subsets, Cardinality

## TL;DR

Power sets are the sets that contain all possible subsets of a given set.

## Key Insights

• 😊 Power sets are the set of all subsets of a given set, which means they contain every possible combination of elements from the original set.
• 🤔 In the example given, the set A is defined as {1, 2, 3}, and its power set contains subsets such as the empty set, sets containing individual elements, and sets containing multiple elements.
• 💡 The cardinality of a power set is determined by the formula 2^n, where n is the cardinality of the original set. In this case, the power set of A has a cardinality of 8 (2^3).
• 😅 The power set can be visually represented as the set containing all subsets of A. In this example, the power set is shown with 8 subsets.
• 🧠 It's important to note that every set, including the empty set, has a power set. The power set of the empty set is simply the set containing the empty set itself.
• 🤯 Power sets can be useful in various mathematical concepts, such as combinatorics and set theory, as they allow for the examination and exploration of all possible subsets within a set.
• 📚 Understanding power sets can help provide insights into the nature of sets and their subsets. It helps in identifying and organizing all possible combinations or variations that can be derived from a given set.
• 💭 If you have any questions or need further clarification on power sets, you can leave a comment or request other math-related topics for future videos.

## Transcript

hello everyone welcome back to wrath of math I'm your host Sean and in today's video we'll be going over power sets what our power sets power sets are pretty cool and a massive pain too right so a power set is very simply the set of all subsets of a particular set so for example let's first define a set we'll define a set a let's start off easy let... Read More

### Q: What is a power set?

A power set is a set that contains all possible subsets of a given set. It includes the empty set and all subsets that contain elements present in the original set.

### Q: How is the cardinality of a power set determined?

The cardinality of a power set is equal to 2 raised to the power of n, where n is the cardinality of the original set. This means that the number of subsets in a power set grows exponentially with the size of the original set.

### Q: Can the power set of the empty set be determined?

Yes, the power set of the empty set contains only the empty set itself. Since there are no elements in the empty set, it can only have one subset, which is the empty set.

### Q: What is the relationship between a set and its power set?

A power set is formed by considering all possible subsets of a given set. This means that every set, including the original set itself and the empty set, is also a subset of its power set.

### Q: How can the cardinality of a power set be used to verify its correctness?

The cardinality of a power set can be determined using the formula 2^n, where n is the cardinality of the original set. By comparing the number of subsets in the power set to the expected cardinality, one can verify if all necessary elements are included.

### Q: Are power sets applicable to any type of set?

Yes, power sets can be formed for any type of set, including sets containing numbers, objects, or any other elements. The concept of power sets is a fundamental concept in set theory.

### Q: How can power sets be useful in mathematics?

Power sets have various applications in mathematics, including areas such as combinatorics, probability theory, and set operations. They allow for the exploration of all possible subsets of a set, enabling the analysis of different configurations and combinations.

### Q: Can power sets be used in computer science or programming?

Yes, power sets can be used in computer science and programming for tasks such as generating all possible subsets of a given set, finding combinations, and solving certain optimization problems. The efficient calculation of power sets can be achieved using algorithms and data structures.

## Summary & Key Takeaways

• Power sets are the sets that contain all possible subsets of a given set.

• The power set of a set includes the empty set and all subsets that contain elements present in the original set.

• The cardinality of a power set is equal to 2 raised to the power of n, where n is the cardinality of the original set.