Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > elsn | Structured version Visualization version GIF version |
Description: There is exactly one element in a singleton. Exercise 2 of [TakeutiZaring] p. 15. (Contributed by NM, 13-Sep-1995.) |
Ref | Expression |
---|---|
elsn.1 | ⊢ 𝐴 ∈ V |
Ref | Expression |
---|---|
elsn | ⊢ (𝐴 ∈ {𝐵} ↔ 𝐴 = 𝐵) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elsn.1 | . 2 ⊢ 𝐴 ∈ V | |
2 | elsng 4567 | . 2 ⊢ (𝐴 ∈ V → (𝐴 ∈ {𝐵} ↔ 𝐴 = 𝐵)) | |
3 | 1, 2 | ax-mp 5 | 1 ⊢ (𝐴 ∈ {𝐵} ↔ 𝐴 = 𝐵) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 208 = wceq 1537 ∈ wcel 2114 Vcvv 3486 {csn 4553 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1796 ax-4 1810 ax-5 1911 ax-6 1970 ax-7 2015 ax-8 2116 ax-9 2124 ax-10 2145 ax-11 2161 ax-12 2177 ax-ext 2793 |
This theorem depends on definitions: df-bi 209 df-an 399 df-or 844 df-tru 1540 df-ex 1781 df-nf 1785 df-sb 2070 df-clab 2800 df-cleq 2814 df-clel 2893 df-nfc 2963 df-sn 4554 |
This theorem is referenced by: velsn 4569 opthwiener 5390 opthprc 5602 dmsnn0 6050 dmsnopg 6056 cnvcnvsn 6062 snsn0non 6295 funconstss 6812 fniniseg 6816 fniniseg2 6818 fsn 6883 fconstfv 6961 eusvobj2 7135 fnse 7813 wfrlem14 7954 fisn 8877 axdc3lem4 9861 axdc4lem 9863 axcclem 9865 opelreal 10538 seqid3 13404 seqz 13408 1exp 13448 hashf1lem2 13804 fprodn0f 15330 imasaddfnlem 16784 initoid 17248 termoid 17249 0subm 17965 smndex1mgm 18055 smndex1n0mnd 18060 grpinvfval 18125 0subg 18287 0nsg 18304 sylow2alem2 18726 gsumval3 19010 gsumzaddlem 19024 kerf1ghm 19480 kerf1hrmOLD 19481 lsssn0 19702 r0cld 22329 alexsubALTlem2 22639 tgphaus 22708 isusp 22853 i1f1lem 24273 ig1pcl 24755 plyco0 24768 plyeq0lem 24786 plycj 24853 wilthlem2 25632 dchrfi 25817 snstriedgval 26809 incistruhgr 26850 1loopgrnb0 27270 umgr2v2enb1 27294 usgr2pthlem 27530 hsn0elch 29009 h1de2ctlem 29316 atomli 30143 brsnop 30415 1stpreimas 30427 gsummpt2d 30694 kerunit 30903 qqhval2lem 31229 qqhf 31234 qqhre 31268 esum2dlem 31358 eulerpartlemb 31633 bnj149 32154 subfacp1lem6 32439 ellimits 33378 bj-0nel1 34281 bj-isrvec 34591 poimirlem18 34944 poimirlem21 34947 poimirlem22 34948 poimirlem31 34957 poimirlem32 34958 itg2addnclem2 34978 ftc1anclem3 35001 0idl 35335 keridl 35342 smprngopr 35362 isdmn3 35384 ellkr 36257 diblss 38338 dihmeetlem4preN 38474 dihmeetlem13N 38487 0prjspnrel 39361 pw2f1ocnv 39726 fvnonrel 40047 snhesn 40222 unirnmapsn 41567 sge0fodjrnlem 42788 lindslinindsimp1 44597 |
Copyright terms: Public domain | W3C validator |