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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 786 |
. . . . 5
| |
| 2 | eldifn 3327 |
. . . . . 6
| |
| 3 | eldifn 3327 |
. . . . . 6
| |
| 4 | 2, 3 | anim12i 338 |
. . . . 5
|
| 5 | 1, 4 | nsyl 631 |
. . . 4
|
| 6 | elin 3387 |
. . . 4
| |
| 7 | 5, 6 | sylnibr 681 |
. . 3
|
| 8 | elun 3345 |
. . 3
| |
| 9 | vex 2802 |
. . . 4
| |
| 10 | eldif 3206 |
. . . 4
| |
| 11 | 9, 10 | mpbiran 946 |
. . 3
|
| 12 | 7, 8, 11 | 3imtr4i 201 |
. 2
|
| 13 | 12 | ssriv 3228 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| 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-in1 617 ax-in2 618 ax-io 714 ax-5 1493 ax-7 1494 ax-gen 1495 ax-ie1 1539 ax-ie2 1540 ax-8 1550 ax-10 1551 ax-11 1552 ax-i12 1553 ax-bndl 1555 ax-4 1556 ax-17 1572 ax-i9 1576 ax-ial 1580 ax-i5r 1581 ax-ext 2211 |
| This theorem depends on definitions: df-bi 117 df-tru 1398 df-nf 1507 df-sb 1809 df-clab 2216 df-cleq 2222 df-clel 2225 df-nfc 2361 df-v 2801 df-dif 3199 df-un 3201 df-in 3203 df-ss 3210 |
| This theorem is referenced by: (None) |
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