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Metamath Proof Explorer


Theorem idsymrel

Description: The identity relation is symmetric. (Contributed by AV, 19-Jun-2022)

Ref Expression
Assertion idsymrel SymRel I

Proof

Step Hyp Ref Expression
1 cnvi I = I
2 reli Rel I
3 dfsymrel4 ( SymRel I ↔ ( I = I ∧ Rel I ) )
4 1 2 3 mpbir2an SymRel I