Theorem 3p1e4 9202

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 9127	. 2 ⊢ 4 = (3 + 1)
2	1	eqcomi 2210	1 ⊢ (3 + 1) = 4

Syntax hints:   = wceq 1373  (class class class)co 5962  1c1 7956   + caddc 7958  3c3 9118  4c4 9119

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 9127

This theorem is referenced by:  7t6e42  9646  8t5e40  9651  9t5e45  9658  fac4  10910  4bc3eq4  10950  hash4  10991  2exp16  12845  cosq23lt0  15390  binom4  15536