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Related theorems GIF version |
| Description: Symmetry of equinumerosity. Theorem 2 of [Suppes] p. 92. |
| Ref | Expression |
|---|---|
| ensym.1 | ⊢ B ∈ V |
| ensymi.2 | ⊢ A ≈ B |
| Ref | Expression |
|---|---|
| ensymi | ⊢ B ≈ A |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ensymi.2 | . 2 ⊢ A ≈ B | |
| 2 | ensym.1 | . . 3 ⊢ B ∈ V | |
| 3 | 2 | ensym 4410 | . 2 ⊢ (A ≈ B → B ≈ A) |
| 4 | 1, 3 | ax-mp 7 | 1 ⊢ B ≈ A |
| Colors of variables: wff set class |
| Syntax hints: ∈ wcel 956 Vcvv 1807 class class class wbr 2615 ≈ cen 4365 |
| This theorem is referenced by: entr2 4415 entr3 4416 entr4 4417 xpdom3 4442 0sdom1dom 4522 pm54.43 4564 unxpdom2 4837 uncdadom 4913 cdaassen 4922 xpcdaen 4923 xpnnen 7461 unben 7468 aleph1re 7514 aleph1irr 7540 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 960 ax-gen 961 ax-8 962 ax-9 963 ax-10 964 ax-11 965 ax-12 966 ax-13 967 ax-14 968 ax-17 969 ax-4 971 ax-5o 973 ax-6o 976 ax-9o 1121 ax-10o 1138 ax-16 1208 ax-11o 1216 ax-ext 1457 ax-rep 2689 ax-sep 2699 ax-pow 2738 ax-pr 2775 ax-un 2865 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-3an 776 df-ex 979 df-sb 1170 df-eu 1380 df-mo 1381 df-clab 1462 df-cleq 1467 df-clel 1470 df-ne 1584 df-rex 1647 df-v 1808 df-dif 2045 df-un 2046 df-in 2047 df-ss 2049 df-nul 2277 df-pw 2398 df-sn 2408 df-pr 2409 df-op 2412 df-uni 2500 df-br 2616 df-opab 2663 df-id 2832 df-xp 3184 df-rel 3185 df-cnv 3186 df-co 3187 df-dm 3188 df-rn 3189 df-res 3190 df-ima 3191 df-fun 3192 df-fn 3193 df-f 3194 df-f1 3195 df-fo 3196 df-f1o 3197 df-er 4262 df-en 4368 |