Sets: A\B can represent A union B?

  • Thread starter KeepTrying
  • Start date
  • Tags
    Sets Union
In summary, by using the set operation of "A\B" (A occurs but B does not), we can express the operations of union, intersection, and complement. It is important to remember that set difference is not associative, and complement involves two sets, A and the universe of discourse X.
  • #1
KeepTrying
2
0
As a event A\B stands for "A occurs but B does not." Show that the operations of union, intersection and complement can all be expressed using only this operation.[tex]A \backslash B = A \cap \bar{B}[/tex]

So far I have resorted to making a truth table with a bunch of A\B combinations that look at A\B, (A\B)\B, ((A\B)\B)\B), and so on. I don't see anything very interesting with this approach. What is a more logical way to look at this problem? If I could find a "nand" or "nor" combination, then I could make any operator. Do I just have to stumble on to it?

Thanks!
 
Last edited:
Physics news on Phys.org
  • #2
The order I would suggest you do this in is complement, union, intersection. A logical way to organize your work is to use complement in doing union and using union to do intersection. It is important, by the way, to remember that set difference is not associative. That is, (A\B)\C is not in general equal to A\(B\C). However, A\B = (A\B)\B = ((A\B)\B)\B = ..., which you can see from thinking about the elements in those sets.

EDIT: Also, remember that complement is really an operation involving two sets, A and the universe of discourse X.
 
Last edited:
  • #3
Thank you Tedjn. The order you suggested and the tip at the very end helped me solve this problem quickly.
 

Related to Sets: A\B can represent A union B?

What is a set?

A set is a collection of distinct objects or elements that are grouped together based on a common characteristic or property.

What is the union of two sets?

The union of two sets, A and B, is a set that contains all the elements from both sets. It is represented by A∪B.

What does the notation A\B mean?

The notation A\B represents the set of elements that are in set A but not in set B. It is also known as the set difference or relative complement of B in A.

How is A\B different from A∪B?

A∪B includes all the elements from both set A and B, while A\B only includes the elements that are in set A but not in set B.

Can A\B be empty?

Yes, if set A and set B have no common elements, then A\B will be an empty set. This means that there are no elements in A that are not in B, so there is nothing to include in the set difference.

Similar threads

Replies
3
Views
396
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
6
Views
1K
  • Calculus and Beyond Homework Help
Replies
17
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
2K
  • Set Theory, Logic, Probability, Statistics
Replies
4
Views
942
  • Calculus and Beyond Homework Help
Replies
1
Views
2K
  • Calculus and Beyond Homework Help
Replies
10
Views
1K
  • Linear and Abstract Algebra
Replies
9
Views
935
Back
Top