Theorem 3p1e4 9279

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 9204	. 2 |- 4 = ( 3 + 1 )
2	1	eqcomi 2235	1 |- ( 3 + 1 ) = 4

Syntax hints:   = wceq 1397  (class class class)co 6018   1c1 8033   + caddc 8035   3c3 9195   4c4 9196

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1495  ax-gen 1497  ax-ext 2213

This theorem depends on definitions:  df-bi 117  df-cleq 2224  df-4 9204

This theorem is referenced by:  7t6e42  9723  8t5e40  9728  9t5e45  9735  fac4  10995  4bc3eq4  11035  hash4  11078  2exp16  13011  cosq23lt0  15559  binom4  15705