Theorem 3p1e4 9171

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 9096	. 2 ⊢ 4 = (3 + 1)
2	1	eqcomi 2208	1 ⊢ (3 + 1) = 4

Syntax hints:   = wceq 1372  (class class class)co 5943  1c1 7925   + caddc 7927  3c3 9087  4c4 9088

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 1469  ax-gen 1471  ax-ext 2186

This theorem depends on definitions:  df-bi 117  df-cleq 2197  df-4 9096

This theorem is referenced by:  7t6e42  9615  8t5e40  9620  9t5e45  9627  fac4  10876  4bc3eq4  10916  hash4  10957  2exp16  12702  cosq23lt0  15247  binom4  15393