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Theorem dfoprab3 4107
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 3986 . 2 |- {<.<.x, y>., z>. | ph} = {<.w, z>. | E.xE.y(w = <.x, y>. /\ ph)}
2 fvex 3727 . . . . . 6 |- (1st` w) e. V
32hbsbc1v 1947 . . . . 5 |- ([(1st` w) / x][(2nd` w) / y]ph -> A.x[(1st` w) / x][(2nd` w) / y]ph)
4319.41 1094 . . . 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 3719 . . . . . . . . . . 11 |- (w = <.x, y>. -> (2nd` w) = (2nd` <.x, y>.))
6 visset 1810 . . . . . . . . . . . 12 |- x e. V
7 visset 1810 . . . . . . . . . . . 12 |- y e. V
86, 7op2nd 4079 . . . . . . . . . . 11 |- (2nd` <.x, y>.) = y
95, 8syl6req 1522 . . . . . . . . . 10 |- (w = <.x, y>. -> y = (2nd`
w))
10 sbceq1a 1941 . . . . . . . . . 10 |- (y = (2nd`
w) -> (ph <-> [(2nd` w) / y]ph))
119, 10syl 10 . . . . . . . . 9 |- (w = <.x, y>. -> (ph <-> [(2nd` w) / y]ph))
12 fveq2 3719 . . . . . . . . . . 11 |- (w = <.x, y>. -> (1st` w) = (1st` <.x, y>.))
136op1st 4078 . . . . . . . . . . 11 |- (1st` <.x, y>.) = x
1412, 13syl6req 1522 . . . . . . . . . 10 |- (w = <.x, y>. -> x = (1st`
w))
15 sbceq1a 1941 . . . . . . . . . 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 527 . . . . . . . 8 |- (w = <.x, y>. -> (ph <-> [(1st` w) / x][(2nd`
w) / y]ph))
1817pm5.32i 644 . . . . . . 7 |- ((w = <.x, y>. /\ ph) <-> (w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
1918exbii 1050 . . . . . 6 |- (E.y(w = <.x, y>. /\ ph) <-> E.y(w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
20 ax-17 970 . . . . . . . . 9 |- (x e. (1st` w) -> A.y x e. (1st` w))
21 fvex 3727 . . . . . . . . . 10 |- (2nd` w) e. V
2221hbsbc1v 1947 . . . . . . . . 9 |- ([(2nd` w) / y]ph -> A.y[(2nd` w) / y]ph)
2320, 22hbsbcg 1948 . . . . . . . 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 1094 . . . . . 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 1050 . . . 4 |- (E.xE.y(w = <.x, y>. /\ ph) <-> E.x(E.y w = <.x, y>. /\ [(1st` w) / x][(2nd` w) / y]ph))
28 elvv 3224 . . . . 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 2667 . 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 1493 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 953   = wceq 955   e. wcel 957  E.wex 979  [wsbc 1169  Vcvv 1808  <.cop 2408  {copab 2662   X. cxp 3164  ` cfv 3178  {copab2 3959  1stc1st 4070  2ndc2nd 4071
This theorem is referenced by:  dfoprab5 4108  eloprabi 4111  foprab2 4112
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 961  ax-gen 962  ax-8 963  ax-9 964  ax-10 965  ax-11 966  ax-12 967  ax-13 968  ax-14 969  ax-17 970  ax-4 972  ax-5o 974  ax-6o 977  ax-9o 1122  ax-10o 1139  ax-16 1209  ax-11o 1217  ax-ext 1458  ax-sep 2699  ax-nul 2706  ax-pow 2738  ax-pr 2775  ax-un 2862
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-ex 980  df-sb 1171  df-eu 1381  df-mo 1382  df-clab 1463  df-cleq 1468  df-clel 1471  df-ne 1585  df-ral 1647  df-rex 1648  df-v 1809  df-sbc 1939  df-dif 2046  df-un 2047  df-in 2048  df-ss 2050  df-nul 2278  df-pw 2399  df-sn 2409  df-pr 2410  df-op 2413  df-uni 2500  df-br 2616  df-opab 2663  df-id 2831  df-xp 3180  df-rel 3181  df-cnv 3182  df-co 3183  df-dm 3184  df-rn 3185  df-res 3186  df-ima 3187  df-fun 3188  df-fv 3194  df-oprab 3961  df-1st 4072  df-2nd 4073
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