Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > elsn2 | Structured version Visualization version GIF version |
Description: There is exactly one element in a singleton. Exercise 2 of [TakeutiZaring] p. 15. This variation requires only that 𝐵, rather than 𝐴, be a set. (Contributed by NM, 12-Jun-1994.) |
Ref | Expression |
---|---|
elsn2.1 | ⊢ 𝐵 ∈ V |
Ref | Expression |
---|---|
elsn2 | ⊢ (𝐴 ∈ {𝐵} ↔ 𝐴 = 𝐵) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elsn2.1 | . 2 ⊢ 𝐵 ∈ V | |
2 | elsn2g 4605 | . 2 ⊢ (𝐵 ∈ 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 3496 {csn 4569 |
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 2795 |
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 2802 df-cleq 2816 df-clel 2895 df-nfc 2965 df-sn 4570 |
This theorem is referenced by: fparlem1 7809 fparlem2 7810 el1o 8126 fin1a2lem11 9834 fin1a2lem12 9835 elnn0 11902 elxnn0 11972 elfzp1 12960 fsumss 15084 fprodss 15304 elhoma 17294 islpidl 20021 zrhrhmb 20660 rest0 21779 qustgphaus 22733 taylfval 24949 elch0 29033 atoml2i 30162 bj-eltag 34291 bj-rest10b 34382 dibopelvalN 38281 dibopelval2 38283 climrec 41891 |
Copyright terms: Public domain | W3C validator |