Theorem 3p1e4 8167

Description: 3 + 1 = 4. (Contributed by Mario Carneiro, 18-Apr-2015.)

Assertion

Ref	Expression
3p1e4	⊢ (3 + 1) = 4

Proof of Theorem 3p1e4

Step	Hyp	Ref	Expression
1		df-4 8100	. 2 ⊢ 4 = (3 + 1)
2	1	eqcomi 2085	1 ⊢ (3 + 1) = 4

Syntax hints:   = wceq 1284  (class class class)co 5532  1c1 6982   + caddc 6984  3c3 8090  4c4 8091

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1376  ax-gen 1378  ax-ext 2063

This theorem depends on definitions:  df-bi 115  df-cleq 2074  df-4 8100

This theorem is referenced by:  7t6e42  8589  8t5e40  8594  9t5e45  8601  fac4  9660  4bc3eq4  9700