Theorem 7p1e8 9444

Description: 7 + 1 = 8. (Contributed by Mario Carneiro, 18-Apr-2015.)

Assertion

Ref	Expression
7p1e8	|- ( 7 + 1 ) = 8

Proof of Theorem 7p1e8

Step	Hyp	Ref	Expression
1		df-8 9369	. 2 |- 8 = ( 7 + 1 )
2	1	eqcomi 2242	1 |- ( 7 + 1 ) = 8

This proof depends on syntax axioms:   = wceq 1402  (class class class)co 6085   1c1 8180   + caddc 8182   7c7 9360   8c8 9361

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-gen 1502  ax-ext 2220

This proof depends on definitions:  df-bi 117  df-cleq 2231  df-8 9369

This theorem is used by:  7t4e28  9887  9t9e81  9905