Is the Symmetric Difference Problem Solved?

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SUMMARY

The discussion centers on the Symmetric Difference Problem, specifically evaluating the validity of two statements involving symmetric difference and intersection. The first statement, \(A\bigtriangleup (B\cap C)=(A\bigtriangleup B)\cap (A\bigtriangleup C)\), and the second, \(A\cup (B\bigtriangleup C)=(A\cup B)\bigtriangleup (A\cup C)\), are both proven false by counterexamples using the universal set as \(A\). The participants clarify the definitions and properties of symmetric difference, leading to a deeper understanding of set operations.

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  • Familiarity with Venn diagrams and their application in set operations.
  • Knowledge of basic set operations: union, intersection, and set difference.
  • Ability to manipulate and interpret mathematical expressions involving sets.
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  • Study the properties of symmetric difference in set theory.
  • Learn how to construct and interpret Venn diagrams for complex set operations.
  • Explore counterexamples in mathematical proofs to strengthen logical reasoning.
  • Investigate advanced set theory topics, such as cardinality and power sets.
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Yankel
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Hello all,

For each of the following statements, I need to say if it is true or not, to prove if it is true or to contradict if not.

1)
\[A\bigtriangleup (B\cap C)=(A\bigtriangleup B)\cap (A\bigtriangleup C)\]

2)
\[A\cup (B\bigtriangleup C)=(A\cup B)\bigtriangleup (A\cup C)\]

Where
\[\bigtriangleup\]

is the symmetric difference.

I do know that:

\[A\bigtriangleup B=(A-B)\cup (B-A)\]

which is:

\[(A\cap B^{C})\cup (B\cap A^{C})\]How do I proceed from here?

Thank you !
 
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Both equations can be refuted by taking $A$ to be the universal set.
 
Is it correct that these are the corresponding Venn diagrams of both sides in the first statement?
(assuming your way, of making A universal).

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