Theorem preq1d 3758

Description: Equality deduction for unordered pairs. (Contributed by NM, 19-Oct-2012.)

Hypothesis

Ref	Expression
preq1d.1	|- ( ph -> A = B )

Assertion

Ref	Expression
preq1d	|- ( ph -> { A , C } = { B , C } )

Proof of Theorem preq1d

Step	Hyp	Ref	Expression
1		preq1d.1	. 2 |- ( ph -> A = B )
2		preq1 3752	. 2 |- ( A = B -> { A , C } = { B , C } )
3	1, 2	syl 14	1 |- ( ph -> { A , C } = { B , C } )

Syntax hints:   -> wi 4   = wceq 1398   {cpr 3674

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-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2213

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-v 2805  df-un 3205  df-sn 3679  df-pr 3680

This theorem is referenced by:  xrbdtri  11899  bdmetval  15294  hovergt0  15444  clwwlk1loop  16323  clwwlkn1  16342