Theorem 3p1e4 9143

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 9068	. 2 ⊢ 4 = (3 + 1)
2	1	eqcomi 2200	1 ⊢ (3 + 1) = 4

Syntax hints:   = wceq 1364  (class class class)co 5925  1c1 7897   + caddc 7899  3c3 9059  4c4 9060

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 1461  ax-gen 1463  ax-ext 2178

This theorem depends on definitions:  df-bi 117  df-cleq 2189  df-4 9068

This theorem is referenced by:  7t6e42  9586  8t5e40  9591  9t5e45  9598  fac4  10842  4bc3eq4  10882  hash4  10923  2exp16  12631  cosq23lt0  15153  binom4  15299