Prove $(A^c)^c$ = $A$
$(A^c)^c = \{x|x\in (A^c)^c\}$
$(A^c)^c = \{x|x\notin A^c\}$ by definition of complement
$(A^c)^c = \{x|\ (x \in A)\}$ by definition of complement
Therefore
$(A^c)^c=A$
Is this proof ok, I'm not sure if its valid? thanks
2026-04-24 22:21:08.1777069268
proof involving double complement
36 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in PROOF-WRITING
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