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Metamath Proof Explorer

Theorem 2p1e3

Description: 2 + 1 = 3. (Contributed by Mario Carneiro, 18-Apr-2015)

Ref Expression
Assertion 2p1e3 ( 2 + 1 ) = 3

Proof

Step Hyp Ref Expression
1 df-3 ⊢ 3 = ( 2 + 1 )
2 1 eqcomi ⊢ ( 2 + 1 ) = 3