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| Mirrors > Home > ILE Home > Th. List > dfcnqs | GIF version | ||
| Description: Technical trick to permit reuse of previous lemmas to prove arithmetic operation laws in ℂ from those in R. The trick involves qsid 6659, which shows that the coset of the converse epsilon relation (which is not an equivalence relation) acts as an identity divisor for the quotient set operation. This lets us "pretend" that ℂ is a quotient set, even though it is not (compare df-c 7885), and allows us to reuse some of the equivalence class lemmas we developed for the transition from positive reals to signed reals, etc. (Contributed by NM, 13-Aug-1995.) | 
| Ref | Expression | 
|---|---|
| dfcnqs | ⊢ ℂ = ((R × R) / ◡ E ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | df-c 7885 | . 2 ⊢ ℂ = (R × R) | |
| 2 | qsid 6659 | . 2 ⊢ ((R × R) / ◡ E ) = (R × R) | |
| 3 | 1, 2 | eqtr4i 2220 | 1 ⊢ ℂ = ((R × R) / ◡ E ) | 
| Colors of variables: wff set class | 
| Syntax hints: = wceq 1364 E cep 4322 × cxp 4661 ◡ccnv 4662 / cqs 6591 Rcnr 7364 ℂcc 7877 | 
| 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-io 710 ax-5 1461 ax-7 1462 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-8 1518 ax-10 1519 ax-11 1520 ax-i12 1521 ax-bndl 1523 ax-4 1524 ax-17 1540 ax-i9 1544 ax-ial 1548 ax-i5r 1549 ax-14 2170 ax-ext 2178 ax-sep 4151 ax-pow 4207 ax-pr 4242 | 
| This theorem depends on definitions: df-bi 117 df-3an 982 df-tru 1367 df-nf 1475 df-sb 1777 df-eu 2048 df-mo 2049 df-clab 2183 df-cleq 2189 df-clel 2192 df-nfc 2328 df-ral 2480 df-rex 2481 df-v 2765 df-sbc 2990 df-un 3161 df-in 3163 df-ss 3170 df-pw 3607 df-sn 3628 df-pr 3629 df-op 3631 df-br 4034 df-opab 4095 df-eprel 4324 df-xp 4669 df-cnv 4671 df-dm 4673 df-rn 4674 df-res 4675 df-ima 4676 df-ec 6594 df-qs 6598 df-c 7885 | 
| This theorem is referenced by: axmulcom 7938 axaddass 7939 axmulass 7940 axdistr 7941 | 
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