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| Mirrors > Home > ILE Home > Th. List > unssin | Unicode version | ||
| Description: Union as a subset of class complement and intersection (De Morgan's law). One direction of the definition of union in [Mendelson] p. 231. This would be an equality, rather than subset, in classical logic. (Contributed by Jim Kingdon, 25-Jul-2018.) |
| Ref | Expression |
|---|---|
| unssin |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | oranim 807 |
. . . . 5
| |
| 2 | eldifn 3067 |
. . . . . 6
| |
| 3 | eldifn 3067 |
. . . . . 6
| |
| 4 | 2, 3 | anim12i 321 |
. . . . 5
|
| 5 | 1, 4 | nsyl 558 |
. . . 4
|
| 6 | elin 3126 |
. . . 4
| |
| 7 | 5, 6 | sylnibr 602 |
. . 3
|
| 8 | elun 3084 |
. . 3
| |
| 9 | vex 2560 |
. . . 4
| |
| 10 | eldif 2927 |
. . . 4
| |
| 11 | 9, 10 | mpbiran 847 |
. . 3
|
| 12 | 7, 8, 11 | 3imtr4i 190 |
. 2
|
| 13 | 12 | ssriv 2949 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 99 ax-ia2 100 ax-ia3 101 ax-in1 544 ax-in2 545 ax-io 630 ax-5 1336 ax-7 1337 ax-gen 1338 ax-ie1 1382 ax-ie2 1383 ax-8 1395 ax-10 1396 ax-11 1397 ax-i12 1398 ax-bndl 1399 ax-4 1400 ax-17 1419 ax-i9 1423 ax-ial 1427 ax-i5r 1428 ax-ext 2022 |
| This theorem depends on definitions: df-bi 110 df-tru 1246 df-nf 1350 df-sb 1646 df-clab 2027 df-cleq 2033 df-clel 2036 df-nfc 2167 df-v 2559 df-dif 2920 df-un 2922 df-in 2924 df-ss 2931 |
| This theorem is referenced by: (None) |
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