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Theorem opkth1g 4130
Description: Equality of the first member of a Kuratowski ordered pair, which holds regardless of the sethood of the second members. (Contributed by SF, 12-Jan-2015.)
Assertion
Ref Expression
opkth1g

Proof of Theorem opkth1g
StepHypRef Expression
1 eqid 2353 . . . . 5
21orci 379 . . . 4
3 elopk 4129 . . . 4
42, 3mpbir 200 . . 3
5 eleq2 2414 . . . . 5
65biimprd 214 . . . 4
7 elopk 4129 . . . . 5
8 snidg 3758 . . . . . . 7
9 eleq2 2414 . . . . . . 7
108, 9syl5ibrcom 213 . . . . . 6
11 prid1g 3825 . . . . . . 7
12 eleq2 2414 . . . . . . 7
1311, 12syl5ibrcom 213 . . . . . 6
1410, 13jaod 369 . . . . 5
157, 14syl5bi 208 . . . 4
166, 15sylan9r 639 . . 3
174, 16mpi 16 . 2
18 elsncg 3755 . . 3
1918adantr 451 . 2
2017, 19mpbid 201 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   wb 176   wo 357   wa 358   wceq 1642   wcel 1710  csn 3737  cpr 3738  copk 4057
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334  ax-nin 4078  ax-sn 4087
This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2478  df-ne 2518  df-v 2861  df-nin 3211  df-compl 3212  df-in 3213  df-un 3214  df-dif 3215  df-ss 3259  df-nul 3551  df-sn 3741  df-pr 3742  df-opk 4058
This theorem is referenced by:  opkthg  4131
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