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| Mirrors > Home > MPE Home > Th. List > Mathboxes > reuprpr | Structured version Visualization version GIF version | ||
| Description: There is a unique proper unordered pair fulfilling a wff iff there are uniquely two different sets fulfilling a corresponding wff. (Contributed by AV, 30-Apr-2023.) | 
| Ref | Expression | 
|---|---|
| reupr.a | ⊢ (𝑝 = {𝑎, 𝑏} → (𝜓 ↔ 𝜒)) | 
| reupr.x | ⊢ (𝑝 = {𝑥, 𝑦} → (𝜓 ↔ 𝜃)) | 
| Ref | Expression | 
|---|---|
| reuprpr | ⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairsproper‘𝑋)𝜓 ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})))) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | prprsprreu 47506 | . 2 ⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairsproper‘𝑋)𝜓 ↔ ∃!𝑝 ∈ (Pairs‘𝑋)((♯‘𝑝) = 2 ∧ 𝜓))) | |
| 2 | fveqeq2 6915 | . . . . 5 ⊢ (𝑝 = {𝑎, 𝑏} → ((♯‘𝑝) = 2 ↔ (♯‘{𝑎, 𝑏}) = 2)) | |
| 3 | hashprg 14434 | . . . . . 6 ⊢ ((𝑎 ∈ V ∧ 𝑏 ∈ V) → (𝑎 ≠ 𝑏 ↔ (♯‘{𝑎, 𝑏}) = 2)) | |
| 4 | 3 | el2v 3487 | . . . . 5 ⊢ (𝑎 ≠ 𝑏 ↔ (♯‘{𝑎, 𝑏}) = 2) | 
| 5 | 2, 4 | bitr4di 289 | . . . 4 ⊢ (𝑝 = {𝑎, 𝑏} → ((♯‘𝑝) = 2 ↔ 𝑎 ≠ 𝑏)) | 
| 6 | reupr.a | . . . 4 ⊢ (𝑝 = {𝑎, 𝑏} → (𝜓 ↔ 𝜒)) | |
| 7 | 5, 6 | anbi12d 632 | . . 3 ⊢ (𝑝 = {𝑎, 𝑏} → (((♯‘𝑝) = 2 ∧ 𝜓) ↔ (𝑎 ≠ 𝑏 ∧ 𝜒))) | 
| 8 | fveqeq2 6915 | . . . . 5 ⊢ (𝑝 = {𝑥, 𝑦} → ((♯‘𝑝) = 2 ↔ (♯‘{𝑥, 𝑦}) = 2)) | |
| 9 | hashprg 14434 | . . . . . 6 ⊢ ((𝑥 ∈ V ∧ 𝑦 ∈ V) → (𝑥 ≠ 𝑦 ↔ (♯‘{𝑥, 𝑦}) = 2)) | |
| 10 | 9 | el2v 3487 | . . . . 5 ⊢ (𝑥 ≠ 𝑦 ↔ (♯‘{𝑥, 𝑦}) = 2) | 
| 11 | 8, 10 | bitr4di 289 | . . . 4 ⊢ (𝑝 = {𝑥, 𝑦} → ((♯‘𝑝) = 2 ↔ 𝑥 ≠ 𝑦)) | 
| 12 | reupr.x | . . . 4 ⊢ (𝑝 = {𝑥, 𝑦} → (𝜓 ↔ 𝜃)) | |
| 13 | 11, 12 | anbi12d 632 | . . 3 ⊢ (𝑝 = {𝑥, 𝑦} → (((♯‘𝑝) = 2 ∧ 𝜓) ↔ (𝑥 ≠ 𝑦 ∧ 𝜃))) | 
| 14 | 7, 13 | reupr 47509 | . 2 ⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairs‘𝑋)((♯‘𝑝) = 2 ∧ 𝜓) ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 ((𝑎 ≠ 𝑏 ∧ 𝜒) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})))) | 
| 15 | df-3an 1089 | . . . . 5 ⊢ ((𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})) ↔ ((𝑎 ≠ 𝑏 ∧ 𝜒) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏}))) | |
| 16 | 15 | bicomi 224 | . . . 4 ⊢ (((𝑎 ≠ 𝑏 ∧ 𝜒) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})) ↔ (𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏}))) | 
| 17 | 16 | a1i 11 | . . 3 ⊢ (𝑋 ∈ 𝑉 → (((𝑎 ≠ 𝑏 ∧ 𝜒) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})) ↔ (𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})))) | 
| 18 | 17 | 2rexbidv 3222 | . 2 ⊢ (𝑋 ∈ 𝑉 → (∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 ((𝑎 ≠ 𝑏 ∧ 𝜒) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})) ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})))) | 
| 19 | 1, 14, 18 | 3bitrd 305 | 1 ⊢ (𝑋 ∈ 𝑉 → (∃!𝑝 ∈ (Pairsproper‘𝑋)𝜓 ↔ ∃𝑎 ∈ 𝑋 ∃𝑏 ∈ 𝑋 (𝑎 ≠ 𝑏 ∧ 𝜒 ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 ((𝑥 ≠ 𝑦 ∧ 𝜃) → {𝑥, 𝑦} = {𝑎, 𝑏})))) | 
| Colors of variables: wff setvar class | 
| Syntax hints: → wi 4 ↔ wb 206 ∧ wa 395 ∧ w3a 1087 = wceq 1540 ∈ wcel 2108 ≠ wne 2940 ∀wral 3061 ∃wrex 3070 ∃!wreu 3378 Vcvv 3480 {cpr 4628 ‘cfv 6561 2c2 12321 ♯chash 14369 Pairscspr 47464 Pairspropercprpr 47499 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1795 ax-4 1809 ax-5 1910 ax-6 1967 ax-7 2007 ax-8 2110 ax-9 2118 ax-10 2141 ax-11 2157 ax-12 2177 ax-ext 2708 ax-rep 5279 ax-sep 5296 ax-nul 5306 ax-pow 5365 ax-pr 5432 ax-un 7755 ax-cnex 11211 ax-resscn 11212 ax-1cn 11213 ax-icn 11214 ax-addcl 11215 ax-addrcl 11216 ax-mulcl 11217 ax-mulrcl 11218 ax-mulcom 11219 ax-addass 11220 ax-mulass 11221 ax-distr 11222 ax-i2m1 11223 ax-1ne0 11224 ax-1rid 11225 ax-rnegex 11226 ax-rrecex 11227 ax-cnre 11228 ax-pre-lttri 11229 ax-pre-lttrn 11230 ax-pre-ltadd 11231 ax-pre-mulgt0 11232 | 
| This theorem depends on definitions: df-bi 207 df-an 396 df-or 849 df-3or 1088 df-3an 1089 df-tru 1543 df-fal 1553 df-ex 1780 df-nf 1784 df-sb 2065 df-mo 2540 df-eu 2569 df-clab 2715 df-cleq 2729 df-clel 2816 df-nfc 2892 df-ne 2941 df-nel 3047 df-ral 3062 df-rex 3071 df-rmo 3380 df-reu 3381 df-rab 3437 df-v 3482 df-sbc 3789 df-csb 3900 df-dif 3954 df-un 3956 df-in 3958 df-ss 3968 df-pss 3971 df-nul 4334 df-if 4526 df-pw 4602 df-sn 4627 df-pr 4629 df-op 4633 df-uni 4908 df-int 4947 df-iun 4993 df-br 5144 df-opab 5206 df-mpt 5226 df-tr 5260 df-id 5578 df-eprel 5584 df-po 5592 df-so 5593 df-fr 5637 df-we 5639 df-xp 5691 df-rel 5692 df-cnv 5693 df-co 5694 df-dm 5695 df-rn 5696 df-res 5697 df-ima 5698 df-pred 6321 df-ord 6387 df-on 6388 df-lim 6389 df-suc 6390 df-iota 6514 df-fun 6563 df-fn 6564 df-f 6565 df-f1 6566 df-fo 6567 df-f1o 6568 df-fv 6569 df-riota 7388 df-ov 7434 df-oprab 7435 df-mpo 7436 df-om 7888 df-1st 8014 df-2nd 8015 df-frecs 8306 df-wrecs 8337 df-recs 8411 df-rdg 8450 df-1o 8506 df-oadd 8510 df-er 8745 df-en 8986 df-dom 8987 df-sdom 8988 df-fin 8989 df-dju 9941 df-card 9979 df-pnf 11297 df-mnf 11298 df-xr 11299 df-ltxr 11300 df-le 11301 df-sub 11494 df-neg 11495 df-nn 12267 df-2 12329 df-n0 12527 df-z 12614 df-uz 12879 df-fz 13548 df-hash 14370 df-spr 47465 df-prpr 47500 | 
| This theorem is referenced by: (None) | 
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