Symmetric Difference if/then Proof

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The discussion centers on proving the statement that if X ⊕ Y = Y ⊕ X, then X must equal Y, where ⊕ denotes the symmetric difference of sets. Participants clarify that X and Y are sets and that ⊕ represents the symmetric difference, which is commutative. One contributor points out that the proof is flawed because the commutative property of symmetric difference implies that X ⊕ Y = Y ⊕ X holds true for any sets X and Y, without necessitating that X equals Y. The conversation emphasizes the need for a deeper understanding of the operations involved. Overall, the initial assertion about the equality of sets based on their symmetric difference is incorrect.
pingi
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Hi there,

I'm trying to figure out proving the following:
if X oplus Y = Y oplus X then X = Y

In order to prove it, I need to use the symmetric difference associativity & other characteristics and identities.

Can you please give me a direction?
Please explain the answer as a teacher would, as my skills of proving this kind of arguments are poor.

Thanks! Pingi.
 
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What is oplus? Also what kind of things are X and Y (sets, logical variables, other things)?
 
Hi mathman,

Sorry for being unclear about my question and thanks for directing me!

1. X and Y are sets.
2. 'oplus' is an add symbol in circle - ⊕, used to describe the symmetric difference of the two sets (with the XOR operation).

Pingi.
 
If it is referring to the symmetric difference or to the exclusive or operations, then I actually don't believe the statement you are trying to prove is true. Both of these operations are commutative, which means that:

X "oplus" Y = Y "oplus" X

regardless of what X and Y are.

If "oplus" means something different, however, then please explain it in more depth.
 
The standard _A " operator" maps a Null Hypothesis Ho into a decision set { Do not reject:=1 and reject :=0}. In this sense ( HA)_A , makes no sense. Since H0, HA aren't exhaustive, can we find an alternative operator, _A' , so that ( H_A)_A' makes sense? Isn't Pearson Neyman related to this? Hope I'm making sense. Edit: I was motivated by a superficial similarity of the idea with double transposition of matrices M, with ## (M^{T})^{T}=M##, and just wanted to see if it made sense to talk...

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