Theorem 3p1e4 9071

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 8997	. 2 |- 4 = ( 3 + 1 )
2	1	eqcomi 2192	1 |- ( 3 + 1 ) = 4

Syntax hints:   = wceq 1363  (class class class)co 5890   1c1 7829   + caddc 7831   3c3 8988   4c4 8989

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 1457  ax-gen 1459  ax-ext 2170

This theorem depends on definitions:  df-bi 117  df-cleq 2181  df-4 8997

This theorem is referenced by:  7t6e42  9513  8t5e40  9518  9t5e45  9525  fac4  10730  4bc3eq4  10770  hash4  10811  cosq23lt0  14637  binom4  14780