Theorem bcxmaslem1 11415

Description: Lemma for bcxmas 11416. (Contributed by Paul Chapman, 18-May-2007.)

Assertion

Ref	Expression
bcxmaslem1	|- ( A = B -> ( ( N + A ) _C A ) = ( ( N + B ) _C B ) )

Proof of Theorem bcxmaslem1

Step	Hyp	Ref	Expression
1		oveq2 5844	. 2 |- ( A = B -> ( N + A ) = ( N + B ) )
2		id 19	. 2 |- ( A = B -> A = B )
3	1, 2	oveq12d 5854	1 |- ( A = B -> ( ( N + A ) _C A ) = ( ( N + B ) _C B ) )

Syntax hints:   -> wi 4   = wceq 1342  (class class class)co 5836   + caddc 7747   _C cbc 10649

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1434  ax-7 1435  ax-gen 1436  ax-ie1 1480  ax-ie2 1481  ax-8 1491  ax-10 1492  ax-11 1493  ax-i12 1494  ax-bndl 1496  ax-4 1497  ax-17 1513  ax-i9 1517  ax-ial 1521  ax-i5r 1522  ax-ext 2146

This theorem depends on definitions:  df-bi 116  df-3an 969  df-tru 1345  df-nf 1448  df-sb 1750  df-clab 2151  df-cleq 2157  df-clel 2160  df-nfc 2295  df-rex 2448  df-v 2723  df-un 3115  df-sn 3576  df-pr 3577  df-op 3579  df-uni 3784  df-br 3977  df-iota 5147  df-fv 5190  df-ov 5839

This theorem is referenced by:  bcxmas  11416