Theorem gsumcllem 19824

Description: Lemma for gsumcl 19831 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 6951	. . 3 ⊢ (𝜑 → 𝐹 = (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)))
3	2	adantr 480	. 2 ⊢ ((𝜑 ∧ 𝑊 = ∅) → 𝐹 = (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)))
4		difeq2 4109	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝐴 ∖ 𝑊) = (𝐴 ∖ ∅))
5		dif0 4365	. . . . . . . 8 ⊢ (𝐴 ∖ ∅) = 𝐴
6	4, 5	eqtrdi 2780	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝐴 ∖ 𝑊) = 𝐴)
7	6	eleq2d 2811	. . . . . 6 ⊢ (𝑊 = ∅ → (𝑘 ∈ (𝐴 ∖ 𝑊) ↔ 𝑘 ∈ 𝐴))
8	7	biimpar 477	. . . . 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 8176	. . . . 5 ⊢ ((𝜑 ∧ 𝑘 ∈ (𝐴 ∖ 𝑊)) → (𝐹‘𝑘) = 𝑍)
13	8, 12	sylan2 592	. . . 4 ⊢ ((𝜑 ∧ (𝑊 = ∅ ∧ 𝑘 ∈ 𝐴)) → (𝐹‘𝑘) = 𝑍)
14	13	anassrs 467	. . 3 ⊢ (((𝜑 ∧ 𝑊 = ∅) ∧ 𝑘 ∈ 𝐴) → (𝐹‘𝑘) = 𝑍)
15	14	mpteq2dva 5239	. 2 ⊢ ((𝜑 ∧ 𝑊 = ∅) → (𝑘 ∈ 𝐴 ↦ (𝐹‘𝑘)) = (𝑘 ∈ 𝐴 ↦ 𝑍))
16	3, 15	eqtrd 2764	1 ⊢ ((𝜑 ∧ 𝑊 = ∅) → 𝐹 = (𝑘 ∈ 𝐴 ↦ 𝑍))

Syntax hints:   → wi 4   ∧ wa 395   = wceq 1533   ∈ wcel 2098   ∖ cdif 3938   ⊆ wss 3941  ∅c0 4315   ↦ cmpt 5222  ⟶wf 6530  ‘cfv 6534  (class class class)co 7402   supp csupp 8141

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1905  ax-6 1963  ax-7 2003  ax-8 2100  ax-9 2108  ax-10 2129  ax-11 2146  ax-12 2163  ax-ext 2695  ax-rep 5276  ax-sep 5290  ax-nul 5297  ax-pr 5418  ax-un 7719

This theorem depends on definitions:  df-bi 206  df-an 396  df-or 845  df-3an 1086  df-tru 1536  df-fal 1546  df-ex 1774  df-nf 1778  df-sb 2060  df-mo 2526  df-eu 2555  df-clab 2702  df-cleq 2716  df-clel 2802  df-nfc 2877  df-ne 2933  df-ral 3054  df-rex 3063  df-reu 3369  df-rab 3425  df-v 3468  df-sbc 3771  df-csb 3887  df-dif 3944  df-un 3946  df-in 3948  df-ss 3958  df-nul 4316  df-if 4522  df-sn 4622  df-pr 4624  df-op 4628  df-uni 4901  df-iun 4990  df-br 5140  df-opab 5202  df-mpt 5223  df-id 5565  df-xp 5673  df-rel 5674  df-cnv 5675  df-co 5676  df-dm 5677  df-rn 5678  df-res 5679  df-ima 5680  df-iota 6486  df-fun 6536  df-fn 6537  df-f 6538  df-f1 6539  df-fo 6540  df-f1o 6541  df-fv 6542  df-ov 7405  df-oprab 7406  df-mpo 7407  df-supp 8142

This theorem is referenced by:  gsumzres  19825  gsumzcl2  19826  gsumzf1o  19828  gsumzaddlem  19837  gsumzmhm  19853  gsumzoppg  19860