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Metamath Proof Explorer

Theorem 1p1e2

Description: 1 + 1 = 2. (Contributed by NM, 1-Apr-2008)

Ref Expression
Assertion 1p1e2 
|- ( 1 + 1 ) = 2

Proof

Step Hyp Ref Expression
1 df-2 
 |-  2 = ( 1 + 1 )
2 1 eqcomi 
 |-  ( 1 + 1 ) = 2