Metamath Proof Explorer


Theorem icheqid

Description: In an equality for the same setvar variable, the setvar variable is interchangeable by itself. Special case of ichid and icheq without distinct variables restriction. (Contributed by AV, 29-Jul-2023)

Ref Expression
Assertion icheqid xxx=x

Proof

Step Hyp Ref Expression
1 ichid xxx=x