EDB — 23S

[23S]Other operators between sets are:

• the difference

  \[ A⧵ B {\stackrel{.}{=}}\{ x∈ A : x∉ B\} \quad ; \]

• if the set \(A\) is clearly specified by the context, and if \(B⊆ A\), it is common to write \(B^ c{\stackrel{.}{=}}A⧵ B\); \(B^ c\) is said to be the complement of \(B\) in \(A\);

• the symmetric difference

  \[ AΔ B {\stackrel{.}{=}}(A∪ B)⧵ (A∩ B)= (A⧵ B)∪(B⧵ A)= \{ x∈ A∪ B : x∈ A\iff x∉ B\} \quad ; \]

where \(A,B\) are sets.