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Theorem idval 10657
Description: Value of the identity function expressed with the 1st and 2nd functions.
Hypothesis
Ref Expression
idval.1 |- J = (id` T)
Assertion
Ref Expression
idval |- J = (1st` (2nd` T))

Proof of Theorem idval
StepHypRef Expression
1 idval.1 . 2 |- J = (id` T)
2 fo1st 4091 . . . . . 6 |- 1st:V-onto->V
3 fofun 3673 . . . . . 6 |- (1st:V-onto->V -> Fun 1st)
42, 3ax-mp 7 . . . . 5 |- Fun 1st
5 fo2nd 4092 . . . . . 6 |- 2nd:V-onto->V
6 fof 3672 . . . . . 6 |- (2nd:V-onto->V -> 2nd:V-->V)
75, 6ax-mp 7 . . . . 5 |- 2nd:V-->V
8 fvco3 3776 . . . . 5 |- ((Fun 1st /\ 2nd:V-->V /\ T e. V) -> ((1st o. 2nd)` T) = (1st`
(2nd` T)))
94, 7, 8mp3an12 906 . . . 4 |- (T e. V -> ((1st o. 2nd)` T) = (1st`
(2nd` T)))
10 df-ida 10651 . . . . 5 |- id = (1st o. 2nd)
1110fveq1i 3725 . . . 4 |- (id` T) = ((1st o. 2nd)` T)
129, 11syl5eq 1519 . . 3 |- (T e. V -> (id` T) = (1st` (2nd` T)))
13 fvprc 3721 . . . 4 |- (-. T e. V -> (id` T) = (/))
14 fvprc 3721 . . . . . 6 |- (-. T e. V -> (2nd` T) = (/))
1514fveq2d 3728 . . . . 5 |- (-. T e. V -> (1st` (2nd` T)) = (1st` (/)))
16 1st0 4083 . . . . 5 |- (1st` (/)) = (/)
1715, 16syl6req 1524 . . . 4 |- (-. T e. V -> (/) = (1st`
(2nd` T)))
1813, 17eqtrd 1507 . . 3 |- (-. T e. V -> (id` T) = (1st` (2nd` T)))
1912, 18pm2.61i 126 . 2 |- (id` T) = (1st` (2nd`
T))
201, 19eqtr 1495 1 |- J = (1st` (2nd` T))
Colors of variables: wff set class
Syntax hints:  -. wn 2   = wceq 956   e. wcel 958  Vcvv 1811  (/)c0 2280   o. ccom 3174  Fun wfun 3176  -->wf 3178  -onto->wfo 3180  ` cfv 3182  1stc1st 4077  2ndc2nd 4078  idcid_ 10646
This theorem is referenced by:  algi 10660  dedi 10670  dedalg 10676  cati 10688  catded 10697
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-3an 777  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-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-fn 3193  df-f 3194  df-fo 3196  df-fv 3198  df-1st 4079  df-2nd 4080  df-ida 10651
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