Users' Mathboxes Mathbox for Jeff Madsen < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  f1ocan1fv Structured version   Visualization version   GIF version

Theorem f1ocan1fv 34882
Description: Cancel a composition by a bijection by preapplying the converse. (Contributed by Jeff Madsen, 2-Sep-2009.) (Proof shortened by Mario Carneiro, 27-Dec-2014.)
Assertion
Ref Expression
f1ocan1fv ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → ((𝐹𝐺)‘(𝐺𝑋)) = (𝐹𝑋))

Proof of Theorem f1ocan1fv
StepHypRef Expression
1 f1of 6608 . . . 4 (𝐺:𝐴1-1-onto𝐵𝐺:𝐴𝐵)
213ad2ant2 1126 . . 3 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → 𝐺:𝐴𝐵)
3 f1ocnv 6620 . . . . . 6 (𝐺:𝐴1-1-onto𝐵𝐺:𝐵1-1-onto𝐴)
4 f1of 6608 . . . . . 6 (𝐺:𝐵1-1-onto𝐴𝐺:𝐵𝐴)
53, 4syl 17 . . . . 5 (𝐺:𝐴1-1-onto𝐵𝐺:𝐵𝐴)
653ad2ant2 1126 . . . 4 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → 𝐺:𝐵𝐴)
7 simp3 1130 . . . 4 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → 𝑋𝐵)
86, 7ffvelrnd 6844 . . 3 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → (𝐺𝑋) ∈ 𝐴)
9 fvco3 6753 . . 3 ((𝐺:𝐴𝐵 ∧ (𝐺𝑋) ∈ 𝐴) → ((𝐹𝐺)‘(𝐺𝑋)) = (𝐹‘(𝐺‘(𝐺𝑋))))
102, 8, 9syl2anc 584 . 2 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → ((𝐹𝐺)‘(𝐺𝑋)) = (𝐹‘(𝐺‘(𝐺𝑋))))
11 f1ocnvfv2 7025 . . . 4 ((𝐺:𝐴1-1-onto𝐵𝑋𝐵) → (𝐺‘(𝐺𝑋)) = 𝑋)
12113adant1 1122 . . 3 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → (𝐺‘(𝐺𝑋)) = 𝑋)
1312fveq2d 6667 . 2 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → (𝐹‘(𝐺‘(𝐺𝑋))) = (𝐹𝑋))
1410, 13eqtrd 2853 1 ((Fun 𝐹𝐺:𝐴1-1-onto𝐵𝑋𝐵) → ((𝐹𝐺)‘(𝐺𝑋)) = (𝐹𝑋))
Colors of variables: wff setvar class
Syntax hints:  wi 4  w3a 1079   = wceq 1528  wcel 2105  ccnv 5547  ccom 5552  Fun wfun 6342  wf 6344  1-1-ontowf1o 6347  cfv 6348
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1787  ax-4 1801  ax-5 1902  ax-6 1961  ax-7 2006  ax-8 2107  ax-9 2115  ax-10 2136  ax-11 2151  ax-12 2167  ax-ext 2790  ax-sep 5194  ax-nul 5201  ax-pow 5257  ax-pr 5320
This theorem depends on definitions:  df-bi 208  df-an 397  df-or 842  df-3an 1081  df-tru 1531  df-ex 1772  df-nf 1776  df-sb 2061  df-mo 2615  df-eu 2647  df-clab 2797  df-cleq 2811  df-clel 2890  df-nfc 2960  df-ne 3014  df-ral 3140  df-rex 3141  df-rab 3144  df-v 3494  df-sbc 3770  df-dif 3936  df-un 3938  df-in 3940  df-ss 3949  df-nul 4289  df-if 4464  df-sn 4558  df-pr 4560  df-op 4564  df-uni 4831  df-br 5058  df-opab 5120  df-id 5453  df-xp 5554  df-rel 5555  df-cnv 5556  df-co 5557  df-dm 5558  df-rn 5559  df-res 5560  df-ima 5561  df-iota 6307  df-fun 6350  df-fn 6351  df-f 6352  df-f1 6353  df-fo 6354  df-f1o 6355  df-fv 6356
This theorem is referenced by:  f1ocan2fv  34883
  Copyright terms: Public domain W3C validator