Theorem preq2d 3755

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

Hypothesis

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

Assertion

Ref	Expression
preq2d	|- ( ph -> { C , A } = { C , B } )

Proof of Theorem preq2d

Step	Hyp	Ref	Expression
1		preq1d.1	. 2 |- ( ph -> A = B )
2		preq2 3749	. 2 |- ( A = B -> { C , A } = { C , B } )
3	1, 2	syl 14	1 |- ( ph -> { C , A } = { C , B } )

Syntax hints:   -> wi 4   = wceq 1397   {cpr 3670

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 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-ext 2213

This theorem depends on definitions:  df-bi 117  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-v 2804  df-un 3204  df-sn 3675  df-pr 3676

This theorem is referenced by:  opthreg  4654  funopsn  5829  prdsex  13351  gsumprval  13481  clwwlkn2  16271  clwwlknonex2lem1  16287