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Mirrors > Home > NFE Home > Th. List > uni1exg | Unicode version |
Description: The unit union operator preserves sethood. (Contributed by SF, 13-Jan-2015.) |
Ref | Expression |
---|---|
uni1exg |
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Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dfuni12 4291 |
. 2
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2 | vvex 4109 |
. . . 4
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3 | xpkexg 4288 |
. . . 4
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4 | 2, 3 | mpan 651 |
. . 3
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5 | p6exg 4290 |
. . 3
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6 | 4, 5 | syl 15 |
. 2
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7 | 1, 6 | syl5eqel 2437 |
1
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Colors of variables: wff setvar class |
Syntax hints: ![]() ![]() ![]() ![]() |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-3 7 ax-mp 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-xp 4079 ax-cnv 4080 ax-typlower 4086 ax-sn 4087 |
This theorem depends on definitions: df-bi 177 df-or 359 df-an 360 df-3an 936 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-ral 2619 df-rex 2620 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-uni 3892 df-opk 4058 df-1c 4136 df-uni1 4138 df-xpk 4185 df-cnvk 4186 df-p6 4191 |
This theorem is referenced by: uni1ex 4293 uniexg 4316 intexg 4319 coexg 4749 siexg 4752 |
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