- #1
Bashyboy
- 1,421
- 5
To prove that two sets are in fact the same, do I actually have to prove that the two are subsets of each other; or could I prove that they are equivalent by some other means, such as invoking the definitions of the sets?
For instance, the I am trying to show that the binary set operator ##+## is commutative; that is,
## A + B = B + A##,
where
##A + B = (A-B) \cup (B-A)##.
By using the commutative property of the ##\cup## operator, I was able to prove the equality:
##A + B = (A-B) \cup (B-A) = (B-A) \cup (A-B) = B+A##
Is this a valid proof?
For instance, the I am trying to show that the binary set operator ##+## is commutative; that is,
## A + B = B + A##,
where
##A + B = (A-B) \cup (B-A)##.
By using the commutative property of the ##\cup## operator, I was able to prove the equality:
##A + B = (A-B) \cup (B-A) = (B-A) \cup (A-B) = B+A##
Is this a valid proof?