Theorem elbasfv 16544

Description: Utility theorem: reverse closure for any structure defined as a function. (Contributed by Stefan O'Rear, 24-Aug-2015.)

Hypotheses

Ref	Expression
elbasfv.s	⊢ 𝑆 = (𝐹‘𝑍)
elbasfv.b	⊢ 𝐵 = (Base‘𝑆)

Assertion

Ref	Expression
elbasfv	⊢ (𝑋 ∈ 𝐵 → 𝑍 ∈ V)

Proof of Theorem elbasfv

Step	Hyp	Ref	Expression
1		n0i 4299	. 2 ⊢ (𝑋 ∈ 𝐵 → ¬ 𝐵 = ∅)
2		elbasfv.s	. . . . 5 ⊢ 𝑆 = (𝐹‘𝑍)
3		fvprc 6663	. . . . 5 ⊢ (¬ 𝑍 ∈ V → (𝐹‘𝑍) = ∅)
4	2, 3	syl5eq 2868	. . . 4 ⊢ (¬ 𝑍 ∈ V → 𝑆 = ∅)
5	4	fveq2d 6674	. . 3 ⊢ (¬ 𝑍 ∈ V → (Base‘𝑆) = (Base‘∅))
6		elbasfv.b	. . 3 ⊢ 𝐵 = (Base‘𝑆)
7		base0 16536	. . 3 ⊢ ∅ = (Base‘∅)
8	5, 6, 7	3eqtr4g 2881	. 2 ⊢ (¬ 𝑍 ∈ V → 𝐵 = ∅)
9	1, 8	nsyl2 143	1 ⊢ (𝑋 ∈ 𝐵 → 𝑍 ∈ V)

Syntax hints:  ¬ wn 3   → wi 4   = wceq 1537   ∈ wcel 2114  Vcvv 3494  ∅c0 4291  ‘cfv 6355  Basecbs 16483

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2793  ax-sep 5203  ax-nul 5210  ax-pow 5266  ax-pr 5330

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3an 1085  df-tru 1540  df-ex 1781  df-nf 1785  df-sb 2070  df-mo 2622  df-eu 2654  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ral 3143  df-rex 3144  df-rab 3147  df-v 3496  df-sbc 3773  df-dif 3939  df-un 3941  df-in 3943  df-ss 3952  df-nul 4292  df-if 4468  df-sn 4568  df-pr 4570  df-op 4574  df-uni 4839  df-br 5067  df-opab 5129  df-mpt 5147  df-id 5460  df-xp 5561  df-rel 5562  df-cnv 5563  df-co 5564  df-dm 5565  df-iota 6314  df-fun 6357  df-fv 6363  df-slot 16487  df-base 16489

This theorem is referenced by:  frmdelbas  18018  symginv  18530  symggen  18598  psgneu  18634  psgnpmtr  18638  coe1sfi  20381  frgpcyg  20720  lindfind  20960  q1pval  24747  r1pval  24750  symgsubg  30731