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Theorem dfoprab3 4114
Description: A way to define an operation class abstraction without using existential quantifiers.
Assertion
Ref Expression
dfoprab3 |- {<.<.x, y>., z>. | ph} = {<.w, z>. | (w e. (V X. V) /\ [(1st` w) / x][(2nd`
w) / y]ph)}
Distinct variable groups:   ph,w   x,y,z,w

Proof of Theorem dfoprab3
StepHypRef Expression
1 dfoprab2 3991 . 2 |- {<.<.x, y>., z>. | ph} = {<.w, z>. | E.xE.y(w = <.x, y>. /\ ph)}
2 fvex 3732 . . . . . 6 |- (1st` w) e. V
32hbsbc1v 1950 . . . . 5 |- ([(1st` w) / x][(2nd` w) / y]ph -> A.x[(1st` w) / x][(2nd` w) / y]ph)
4319.41 1095 . . . 4 |- (E.x(E.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph) <-> (E.xE.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
5 fveq2 3724 . . . . . . . . . . 11 |- (w = <.x, y>. -> (2nd` w) = (2nd` <.x, y>.))
6 visset 1813 . . . . . . . . . . . 12 |- x e. V
7 visset 1813 . . . . . . . . . . . 12 |- y e. V
86, 7op2nd 4086 . . . . . . . . . . 11 |- (2nd` <.x, y>.) = y
95, 8syl6req 1524 . . . . . . . . . 10 |- (w = <.x, y>. -> y = (2nd`
w))
10 sbceq1a 1944 . . . . . . . . . 10 |- (y = (2nd`
w) -> (ph <-> [(2nd` w) / y]ph))
119, 10syl 10 . . . . . . . . 9 |- (w = <.x, y>. -> (ph <-> [(2nd` w) / y]ph))
12 fveq2 3724 . . . . . . . . . . 11 |- (w = <.x, y>. -> (1st` w) = (1st` <.x, y>.))
136op1st 4085 . . . . . . . . . . 11 |- (1st` <.x, y>.) = x
1412, 13syl6req 1524 . . . . . . . . . 10 |- (w = <.x, y>. -> x = (1st`
w))
15 sbceq1a 1944 . . . . . . . . . 10 |- (x = (1st`
w) -> ([(2nd`
w) / y]ph <-> [(1st` w) / x][(2nd` w) / y]ph))
1614, 15syl 10 . . . . . . . . 9 |- (w = <.x, y>. -> ([(2nd` w) / y]ph <-> [(1st` w) / x][(2nd`
w) / y]ph))
1711, 16bitrd 528 . . . . . . . 8 |- (w = <.x, y>. -> (ph <-> [(1st` w) / x][(2nd`
w) / y]ph))
1817pm5.32i 645 . . . . . . 7 |- ((w = <.x, y>. /\ ph) <-> (w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
1918exbii 1051 . . . . . 6 |- (E.y(w = <.x, y>. /\ ph) <-> E.y(w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
20 ax-17 971 . . . . . . . . 9 |- (x e. (1st` w) -> A.y x e. (1st` w))
21 fvex 3732 . . . . . . . . . 10 |- (2nd` w) e. V
2221hbsbc1v 1950 . . . . . . . . 9 |- ([(2nd` w) / y]ph -> A.y[(2nd` w) / y]ph)
2320, 22hbsbcg 1951 . . . . . . . 8 |- ((1st` w) e. V -> ([(1st` w) / x][(2nd` w) / y]ph -> A.y[(1st` w) / x][(2nd` w) / y]ph))
242, 23ax-mp 7 . . . . . . 7 |- ([(1st` w) / x][(2nd` w) / y]ph -> A.y[(1st` w) / x][(2nd` w) / y]ph)
252419.41 1095 . . . . . 6 |- (E.y(w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph) <-> (E.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
2619, 25bitr 173 . . . . 5 |- (E.y(w = <.x, y>. /\ ph) <-> (E.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
2726exbii 1051 . . . 4 |- (E.xE.y(w = <.x, y>. /\ ph) <-> E.x(E.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
28 elvv 3228 . . . . 5 |- (w e. (V X. V) <-> E.xE.y w = <.x, y>.)
2928anbi1i 481 . . . 4 |- ((w e. (V X. V) /\ [(1st`
w) / x][(2nd`
w) / y]ph) <-> (E.xE.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
304, 27, 293bitr4 183 . . 3 |- (E.xE.y(w = <.x, y>. /\ ph) <-> (w e. (V X. V) /\ [(1st` w) / x][(2nd` w) / y]ph))
3130opabbii 2671 . 2 |- {<.w, z>. | E.xE.y(w = <.x, y>. /\ ph)} = {<.w, z>. | (w e. (V X. V) /\ [(1st` w) / x][(2nd` w) / y]ph)}
321, 31eqtr 1495 1 |- {<.<.x, y>., z>. | ph} = {<.w, z>. | (w e. (V X. V) /\ [(1st` w) / x][(2nd`
w) / y]ph)}
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223  A.wal 954   = wceq 956   e. wcel 958  E.wex 980  [wsbc 1170  Vcvv 1811  <.cop 2411  {copab 2666   X. cxp 3168  ` cfv 3182  {copab2 3964  1stc1st 4077  2ndc2nd 4078
This theorem is referenced by:  dfoprab5 4115  eloprabi 4118  foprab2 4119
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 962  ax-gen 963  ax-8 964  ax-9 965  ax-10 966  ax-11 967  ax-12 968  ax-13 969  ax-14 970  ax-17 971  ax-4 973  ax-5o 975  ax-6o 978  ax-9o 1123  ax-10o 1140  ax-16 1210  ax-11o 1218  ax-ext 1459  ax-sep 2703  ax-nul 2710  ax-pow 2742  ax-pr 2779  ax-un 2866
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-ex 981  df-sb 1172  df-eu 1382  df-mo 1383  df-clab 1464  df-cleq 1469  df-clel 1472  df-ne 1587  df-ral 1649  df-rex 1650  df-v 1812  df-sbc 1942  df-dif 2049  df-un 2050  df-in 2051  df-ss 2053  df-nul 2281  df-pw 2402  df-sn 2412  df-pr 2413  df-op 2416  df-uni 2504  df-br 2620  df-opab 2667  df-id 2835  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-fv 3198  df-oprab 3966  df-1st 4079  df-2nd 4080
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