Theorem elbasfv 16546

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 4301	. 2 ⊢ (𝑋 ∈ 𝐵 → ¬ 𝐵 = ∅)
2		elbasfv.s	. . . . 5 ⊢ 𝑆 = (𝐹‘𝑍)
3		fvprc 6665	. . . . 5 ⊢ (¬ 𝑍 ∈ V → (𝐹‘𝑍) = ∅)
4	2, 3	syl5eq 2870	. . . 4 ⊢ (¬ 𝑍 ∈ V → 𝑆 = ∅)
5	4	fveq2d 6676	. . 3 ⊢ (¬ 𝑍 ∈ V → (Base‘𝑆) = (Base‘∅))
6		elbasfv.b	. . 3 ⊢ 𝐵 = (Base‘𝑆)
7		base0 16538	. . 3 ⊢ ∅ = (Base‘∅)
8	5, 6, 7	3eqtr4g 2883	. 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 3496  ∅c0 4293  ‘cfv 6357  Basecbs 16485

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 2795  ax-sep 5205  ax-nul 5212  ax-pow 5268  ax-pr 5332

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 2802  df-cleq 2816  df-clel 2895  df-nfc 2965  df-ral 3145  df-rex 3146  df-rab 3149  df-v 3498  df-sbc 3775  df-dif 3941  df-un 3943  df-in 3945  df-ss 3954  df-nul 4294  df-if 4470  df-sn 4570  df-pr 4572  df-op 4576  df-uni 4841  df-br 5069  df-opab 5131  df-mpt 5149  df-id 5462  df-xp 5563  df-rel 5564  df-cnv 5565  df-co 5566  df-dm 5567  df-iota 6316  df-fun 6359  df-fv 6365  df-slot 16489  df-base 16491

This theorem is referenced by:  frmdelbas  18020  symginv  18532  symggen  18600  psgneu  18636  psgnpmtr  18640  coe1sfi  20383  frgpcyg  20722  lindfind  20962  q1pval  24749  r1pval  24752  symgsubg  30733