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Theorem eu1 2225
Description: An alternate way to express uniqueness used by some authors. Exercise 2(b) of [Margaris] p. 110. (Contributed by NM, 20-Aug-1993.) (Revised by Mario Carneiro, 7-Oct-2016.)
Hypothesis
Ref Expression
eu1.1  F/
Assertion
Ref Expression
eu1
Distinct variable group:   ,
Allowed substitution hints:   (,)

Proof of Theorem eu1
StepHypRef Expression
1 nfs1v 2106 . . 3  F/
21euf 2210 . 2
3 eu1.1 . . 3  F/
43sb8eu 2222 . 2
5 equcom 1680 . . . . . . 7
65imbi2i 303 . . . . . 6
76albii 1566 . . . . 5
83sb6rf 2091 . . . . 5
97, 8anbi12i 678 . . . 4
10 ancom 437 . . . 4
11 albiim 1611 . . . 4
129, 10, 113bitr4i 268 . . 3
1312exbii 1582 . 2
142, 4, 133bitr4i 268 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   wb 176   wa 358  wal 1540  wex 1541   F/wnf 1544   wceq 1642  wsb 1648  weu 2204
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
This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-eu 2208
This theorem is referenced by:  euex  2227  eu2  2229  fvfullfunlem1  5861
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