Relations and sets

  • Thread starter StIgM@
  • Start date
  • #1
StIgM@
8
0
Hello guys,
I am new to this forum.

I have a question:
A relation can be subset of some other relation?

For example? I have the relations
X: A <---> B
Y: B <---> C
Z: A <---> C

X relational composition Y can be a subset of Z (if Z contains all the pairs of the composition)

Thanks in advance for your help

StIgM@
 

Answers and Replies

  • #2
disregardthat
Science Advisor
1,866
34
A binary relation is a set R of pairs (x,y) such that (x,y) is in R if an only if x is related to y. If x and y are related we write xRy. In general, a n-ary relation in general is a set of n-tuples. A subset of a relation R is merely a subset of the set R.

In set theory we usually define a relation as an ordered triple (A,B,R), where R is a subset of A x B.
 
  • #3
StIgM@
8
0
Ok, I get your meaning but you didn't give an answer to my example!

Do you know if this is correct?

For example? I have the relations
X: A <---> B
Y: B <---> C
Z: A <---> C

X relational composition Y can be a subset of Z (if Z contains all the pairs of the composition)
????
 
  • #4
discrete*
79
0
Ok, I get your meaning but you didn't give an answer to my example!

Do you know if this is correct?

For example? I have the relations
X: A <---> B
Y: B <---> C
Z: A <---> C

X relational composition Y can be a subset of Z (if Z contains all the pairs of the composition)
????

This is not really the right place to post homework-style questions. Also Jarle's post contains the answer to your question in the clever wording of the definition. Good luck, welcome to the forum!
 

Suggested for: Relations and sets

  • Last Post
Replies
1
Views
1K
  • Last Post
2
Replies
62
Views
1K
  • Last Post
Replies
3
Views
3K
  • Last Post
Replies
8
Views
3K
Replies
6
Views
2K
  • Last Post
Replies
1
Views
884
Replies
4
Views
828
Replies
25
Views
7K
Replies
22
Views
14K
Top