Theorem gsumcllem 19775

Description: Lemma for gsumcl 19782 and related theorems. (Contributed by Mario Carneiro, 15-Dec-2014.) (Revised by Mario Carneiro, 24-Apr-2016.) (Revised by AV, 31-May-2019.)

Hypotheses

Ref	Expression
gsumcllem.f	⊢ (𝜑 → 𝐹:𝐴⟶𝐵)
gsumcllem.a	⊢ (𝜑 → 𝐴 ∈ 𝑉)
gsumcllem.z	⊢ (𝜑 → 𝑍 ∈ 𝑈)
gsumcllem.s	⊢ (𝜑 → (𝐹 supp 𝑍) ⊆ 𝑊)

Assertion

Ref	Expression
gsumcllem	⊢ ((𝜑 ∧ 𝑊 = ∅) → 𝐹 = (𝑘 ∈ 𝐴 ↦ 𝑍))

Distinct variable groups:   𝐴,𝑘   𝑘,𝐹   𝜑,𝑘   𝑘,𝑊

Allowed substitution hints:   𝐵(𝑘)   𝑈(𝑘)   𝑉(𝑘)   𝑍(𝑘)

Proof of Theorem gsumcllem

Step	Hyp	Ref	Expression
1		gsumcllem.f	. . . 4 ⊢ (𝜑 → 𝐹:𝐴⟶𝐵)
2	1	feqmptd 6960	. . 3 ⊢ (𝜑 → 𝐹 = (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)))
3	2	adantr 481	. 2 ⊢ ((𝜑 ∧ 𝑊 = ∅) → 𝐹 = (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)))
4		difeq2 4116	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝐴 ∖ 𝑊) = (𝐴 ∖ ∅))
5		dif0 4372	. . . . . . . 8 ⊢ (𝐴 ∖ ∅) = 𝐴
6	4, 5	eqtrdi 2788	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝐴 ∖ 𝑊) = 𝐴)
7	6	eleq2d 2819	. . . . . 6 ⊢ (𝑊 = ∅ → (𝑘 ∈ (𝐴 ∖ 𝑊) ↔ 𝑘 ∈ 𝐴))
8	7	biimpar 478	. . . . 5 ⊢ ((𝑊 = ∅ ∧ 𝑘 ∈ 𝐴) → 𝑘 ∈ (𝐴 ∖ 𝑊))
9		gsumcllem.s	. . . . . 6 ⊢ (𝜑 → (𝐹 supp 𝑍) ⊆ 𝑊)
10		gsumcllem.a	. . . . . 6 ⊢ (𝜑 → 𝐴 ∈ 𝑉)
11		gsumcllem.z	. . . . . 6 ⊢ (𝜑 → 𝑍 ∈ 𝑈)
12	1, 9, 10, 11	suppssr 8180	. . . . 5 ⊢ ((𝜑 ∧ 𝑘 ∈ (𝐴 ∖ 𝑊)) → (𝐹‘𝑘) = 𝑍)
13	8, 12	sylan2 593	. . . 4 ⊢ ((𝜑 ∧ (𝑊 = ∅ ∧ 𝑘 ∈ 𝐴)) → (𝐹‘𝑘) = 𝑍)
14	13	anassrs 468	. . 3 ⊢ (((𝜑 ∧ 𝑊 = ∅) ∧ 𝑘 ∈ 𝐴) → (𝐹‘𝑘) = 𝑍)
15	14	mpteq2dva 5248	. 2 ⊢ ((𝜑 ∧ 𝑊 = ∅) → (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)) = (𝑘 ∈ 𝐴 ↦ 𝑍))
16	3, 15	eqtrd 2772	1 ⊢ ((𝜑 ∧ 𝑊 = ∅) → 𝐹 = (𝑘 ∈ 𝐴 ↦ 𝑍))

Syntax hints:   → wi 4   ∧ wa 396   = wceq 1541   ∈ wcel 2106   ∖ cdif 3945   ⊆ wss 3948  ∅c0 4322   ↦ cmpt 5231  ⟶wf 6539  ‘cfv 6543  (class class class)co 7408   supp csupp 8145

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2703  ax-rep 5285  ax-sep 5299  ax-nul 5306  ax-pr 5427  ax-un 7724

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2534  df-eu 2563  df-clab 2710  df-cleq 2724  df-clel 2810  df-nfc 2885  df-ne 2941  df-ral 3062  df-rex 3071  df-reu 3377  df-rab 3433  df-v 3476  df-sbc 3778  df-csb 3894  df-dif 3951  df-un 3953  df-in 3955  df-ss 3965  df-nul 4323  df-if 4529  df-sn 4629  df-pr 4631  df-op 4635  df-uni 4909  df-iun 4999  df-br 5149  df-opab 5211  df-mpt 5232  df-id 5574  df-xp 5682  df-rel 5683  df-cnv 5684  df-co 5685  df-dm 5686  df-rn 5687  df-res 5688  df-ima 5689  df-iota 6495  df-fun 6545  df-fn 6546  df-f 6547  df-f1 6548  df-fo 6549  df-f1o 6550  df-fv 6551  df-ov 7411  df-oprab 7412  df-mpo 7413  df-supp 8146

This theorem is referenced by:  gsumzres  19776  gsumzcl2  19777  gsumzf1o  19779  gsumzaddlem  19788  gsumzmhm  19804  gsumzoppg  19811