Theorem 3p1e4 9192

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 9117	. 2 ⊢ 4 = (3 + 1)
2	1	eqcomi 2210	1 ⊢ (3 + 1) = 4

Syntax hints:   = wceq 1373  (class class class)co 5957  1c1 7946   + caddc 7948  3c3 9108  4c4 9109

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 1471  ax-gen 1473  ax-ext 2188

This theorem depends on definitions:  df-bi 117  df-cleq 2199  df-4 9117

This theorem is referenced by:  7t6e42  9636  8t5e40  9641  9t5e45  9648  fac4  10900  4bc3eq4  10940  hash4  10981  2exp16  12835  cosq23lt0  15380  binom4  15526