Theorem 3p1e4 9207

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 9132	. 2 |- 4 = ( 3 + 1 )
2	1	eqcomi 2211	1 |- ( 3 + 1 ) = 4

Syntax hints:   = wceq 1373  (class class class)co 5967   1c1 7961   + caddc 7963   3c3 9123   4c4 9124

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 2189

This theorem depends on definitions:  df-bi 117  df-cleq 2200  df-4 9132

This theorem is referenced by:  7t6e42  9651  8t5e40  9656  9t5e45  9663  fac4  10915  4bc3eq4  10955  hash4  10996  2exp16  12875  cosq23lt0  15420  binom4  15566