Users' Mathboxes Mathbox for BJ < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  bj-projun Structured version   Visualization version   GIF version

Theorem bj-projun 33505
Description: The class projection on a given component preserves unions. (Contributed by BJ, 6-Apr-2019.)
Assertion
Ref Expression
bj-projun (𝐴 Proj (𝐵𝐶)) = ((𝐴 Proj 𝐵) ∪ (𝐴 Proj 𝐶))

Proof of Theorem bj-projun
Dummy variable 𝑥 is distinct from all other variables.
StepHypRef Expression
1 df-bj-proj 33502 . . . . 5 (𝐴 Proj 𝐵) = {𝑥 ∣ {𝑥} ∈ (𝐵 “ {𝐴})}
21abeq2i 2941 . . . 4 (𝑥 ∈ (𝐴 Proj 𝐵) ↔ {𝑥} ∈ (𝐵 “ {𝐴}))
3 df-bj-proj 33502 . . . . 5 (𝐴 Proj 𝐶) = {𝑥 ∣ {𝑥} ∈ (𝐶 “ {𝐴})}
43abeq2i 2941 . . . 4 (𝑥 ∈ (𝐴 Proj 𝐶) ↔ {𝑥} ∈ (𝐶 “ {𝐴}))
52, 4orbi12i 945 . . 3 ((𝑥 ∈ (𝐴 Proj 𝐵) ∨ 𝑥 ∈ (𝐴 Proj 𝐶)) ↔ ({𝑥} ∈ (𝐵 “ {𝐴}) ∨ {𝑥} ∈ (𝐶 “ {𝐴})))
6 elun 3981 . . 3 (𝑥 ∈ ((𝐴 Proj 𝐵) ∪ (𝐴 Proj 𝐶)) ↔ (𝑥 ∈ (𝐴 Proj 𝐵) ∨ 𝑥 ∈ (𝐴 Proj 𝐶)))
7 df-bj-proj 33502 . . . . 5 (𝐴 Proj (𝐵𝐶)) = {𝑥 ∣ {𝑥} ∈ ((𝐵𝐶) “ {𝐴})}
87abeq2i 2941 . . . 4 (𝑥 ∈ (𝐴 Proj (𝐵𝐶)) ↔ {𝑥} ∈ ((𝐵𝐶) “ {𝐴}))
9 imaundir 5788 . . . . 5 ((𝐵𝐶) “ {𝐴}) = ((𝐵 “ {𝐴}) ∪ (𝐶 “ {𝐴}))
109eleq2i 2899 . . . 4 ({𝑥} ∈ ((𝐵𝐶) “ {𝐴}) ↔ {𝑥} ∈ ((𝐵 “ {𝐴}) ∪ (𝐶 “ {𝐴})))
11 elun 3981 . . . 4 ({𝑥} ∈ ((𝐵 “ {𝐴}) ∪ (𝐶 “ {𝐴})) ↔ ({𝑥} ∈ (𝐵 “ {𝐴}) ∨ {𝑥} ∈ (𝐶 “ {𝐴})))
128, 10, 113bitri 289 . . 3 (𝑥 ∈ (𝐴 Proj (𝐵𝐶)) ↔ ({𝑥} ∈ (𝐵 “ {𝐴}) ∨ {𝑥} ∈ (𝐶 “ {𝐴})))
135, 6, 123bitr4ri 296 . 2 (𝑥 ∈ (𝐴 Proj (𝐵𝐶)) ↔ 𝑥 ∈ ((𝐴 Proj 𝐵) ∪ (𝐴 Proj 𝐶)))
1413eqriv 2823 1 (𝐴 Proj (𝐵𝐶)) = ((𝐴 Proj 𝐵) ∪ (𝐴 Proj 𝐶))
Colors of variables: wff setvar class
Syntax hints:  wo 880   = wceq 1658  wcel 2166  cun 3797  {csn 4398  cima 5346   Proj bj-cproj 33501
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1896  ax-4 1910  ax-5 2011  ax-6 2077  ax-7 2114  ax-9 2175  ax-10 2194  ax-11 2209  ax-12 2222  ax-13 2391  ax-ext 2804
This theorem depends on definitions:  df-bi 199  df-an 387  df-or 881  df-3an 1115  df-tru 1662  df-ex 1881  df-nf 1885  df-sb 2070  df-clab 2813  df-cleq 2819  df-clel 2822  df-nfc 2959  df-rab 3127  df-v 3417  df-dif 3802  df-un 3804  df-in 3806  df-ss 3813  df-nul 4146  df-if 4308  df-sn 4399  df-pr 4401  df-op 4405  df-br 4875  df-opab 4937  df-cnv 5351  df-dm 5353  df-rn 5354  df-res 5355  df-ima 5356  df-bj-proj 33502
This theorem is referenced by:  bj-pr1un  33514  bj-pr2un  33528
  Copyright terms: Public domain W3C validator