Theorem ressuppfi 8861

Description: If the support of the restriction of a function by a set which, subtracted from the domain of the function so that its difference is finite, the support of the function itself is finite. (Contributed by AV, 22-Apr-2019.)

Hypotheses

Ref	Expression
ressuppfi.b	⊢ (𝜑 → (dom 𝐹 ∖ 𝐵) ∈ Fin)
ressuppfi.f	⊢ (𝜑 → 𝐹 ∈ 𝑊)
ressuppfi.g	⊢ (𝜑 → 𝐺 = (𝐹 ↾ 𝐵))
ressuppfi.s	⊢ (𝜑 → (𝐺 supp 𝑍) ∈ Fin)
ressuppfi.z	⊢ (𝜑 → 𝑍 ∈ 𝑉)

Assertion

Ref	Expression
ressuppfi	⊢ (𝜑 → (𝐹 supp 𝑍) ∈ Fin)

Proof of Theorem ressuppfi

Step	Hyp	Ref	Expression
1		ressuppfi.g	. . . . . 6 ⊢ (𝜑 → 𝐺 = (𝐹 ↾ 𝐵))
2	1	eqcomd 2829	. . . . 5 ⊢ (𝜑 → (𝐹 ↾ 𝐵) = 𝐺)
3	2	oveq1d 7173	. . . 4 ⊢ (𝜑 → ((𝐹 ↾ 𝐵) supp 𝑍) = (𝐺 supp 𝑍))
4		ressuppfi.s	. . . 4 ⊢ (𝜑 → (𝐺 supp 𝑍) ∈ Fin)
5	3, 4	eqeltrd 2915	. . 3 ⊢ (𝜑 → ((𝐹 ↾ 𝐵) supp 𝑍) ∈ Fin)
6		ressuppfi.b	. . 3 ⊢ (𝜑 → (dom 𝐹 ∖ 𝐵) ∈ Fin)
7		unfi 8787	. . 3 ⊢ ((((𝐹 ↾ 𝐵) supp 𝑍) ∈ Fin ∧ (dom 𝐹 ∖ 𝐵) ∈ Fin) → (((𝐹 ↾ 𝐵) supp 𝑍) ∪ (dom 𝐹 ∖ 𝐵)) ∈ Fin)
8	5, 6, 7	syl2anc 586	. 2 ⊢ (𝜑 → (((𝐹 ↾ 𝐵) supp 𝑍) ∪ (dom 𝐹 ∖ 𝐵)) ∈ Fin)
9		ressuppfi.f	. . 3 ⊢ (𝜑 → 𝐹 ∈ 𝑊)
10		ressuppfi.z	. . 3 ⊢ (𝜑 → 𝑍 ∈ 𝑉)
11		ressuppssdif 7853	. . 3 ⊢ ((𝐹 ∈ 𝑊 ∧ 𝑍 ∈ 𝑉) → (𝐹 supp 𝑍) ⊆ (((𝐹 ↾ 𝐵) supp 𝑍) ∪ (dom 𝐹 ∖ 𝐵)))
12	9, 10, 11	syl2anc 586	. 2 ⊢ (𝜑 → (𝐹 supp 𝑍) ⊆ (((𝐹 ↾ 𝐵) supp 𝑍) ∪ (dom 𝐹 ∖ 𝐵)))
13	8, 12	ssfid 8743	1 ⊢ (𝜑 → (𝐹 supp 𝑍) ∈ Fin)

Syntax hints:   → wi 4   = wceq 1537   ∈ wcel 2114   ∖ cdif 3935   ∪ cun 3936   ⊆ wss 3938  dom cdm 5557   ↾ cres 5559  (class class class)co 7158   supp csupp 7832  Fincfn 8511

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  ax-un 7463

This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  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-ne 3019  df-ral 3145  df-rex 3146  df-reu 3147  df-rab 3149  df-v 3498  df-sbc 3775  df-csb 3886  df-dif 3941  df-un 3943  df-in 3945  df-ss 3954  df-pss 3956  df-nul 4294  df-if 4470  df-pw 4543  df-sn 4570  df-pr 4572  df-tp 4574  df-op 4576  df-uni 4841  df-int 4879  df-iun 4923  df-br 5069  df-opab 5131  df-mpt 5149  df-tr 5175  df-id 5462  df-eprel 5467  df-po 5476  df-so 5477  df-fr 5516  df-we 5518  df-xp 5563  df-rel 5564  df-cnv 5565  df-co 5566  df-dm 5567  df-rn 5568  df-res 5569  df-ima 5570  df-pred 6150  df-ord 6196  df-on 6197  df-lim 6198  df-suc 6199  df-iota 6316  df-fun 6359  df-fn 6360  df-f 6361  df-f1 6362  df-fo 6363  df-f1o 6364  df-fv 6365  df-ov 7161  df-oprab 7162  df-mpo 7163  df-om 7583  df-supp 7833  df-wrecs 7949  df-recs 8010  df-rdg 8048  df-oadd 8108  df-er 8291  df-en 8512  df-fin 8515

This theorem is referenced by:  resfsupp  8862