How to show this mathmatically?

  • Thread starter Thread starter Kaldanis
  • Start date Start date
Click For Summary
SUMMARY

The discussion centers on proving the mathematical statement that the difference between sets A and B, denoted as A \ B, is empty (∅) if and only if A is a subset of B (A ⊆ B). The participants clarify that if A is a subset of B, then removing all elements of A from B results in an empty set. The mathematical expression can be formally written as: "For all x in A, x is in B," which establishes the necessary proof.

PREREQUISITES
  • Understanding of set theory concepts, specifically set difference and subset notation.
  • Familiarity with mathematical logic and implications.
  • Basic knowledge of universal quantifiers in mathematical statements.
  • Ability to manipulate and express set relationships mathematically.
NEXT STEPS
  • Study the formal definitions of set difference and subset in set theory.
  • Learn how to use universal quantifiers in mathematical proofs.
  • Explore examples of set proofs involving implications and equivalences.
  • Practice writing formal mathematical proofs for various set relationships.
USEFUL FOR

Students studying set theory, mathematics educators, and anyone interested in formal mathematical proof techniques.

Kaldanis
Messages
106
Reaction score
0

Homework Statement



Let A and B be sets.
Show that A \ B = ∅ if and only if A ⊆ B.


I think this means that A is a subset of B, therefor if I remove all the elements of A that are in B, A would end up being empty (or ∅).

How do I write this mathmatically or is the above sentence acceptable?
 
Physics news on Phys.org
Kaldanis said:

Homework Statement



Let A and B be sets.
Show that A \ B = ∅ if and only if A ⊆ B.I think this means that A is a subset of B, therefor if I remove all the elements of A that are in B, A would end up being empty (or ∅).

How do I write this mathmatically or is the above sentence acceptable?

You would start with something like, A is a subset of B implies for all x in A, x is in B. ...
 

Similar threads

Replies
8
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
6
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
23
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K