Theorem fvelimad 6949

Description: Function value in an image. (Contributed by Glauco Siliprandi, 23-Oct-2021.)

Hypotheses

Ref	Expression
fvelimad.x	⊢ Ⅎ𝑥𝐹
fvelimad.f	⊢ (𝜑 → 𝐹 Fn 𝐴)
fvelimad.c	⊢ (𝜑 → 𝐶 ∈ (𝐹 “ 𝐵))

Assertion

Ref	Expression
fvelimad	⊢ (𝜑 → ∃𝑥 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑥) = 𝐶)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵   𝑥,𝐶

Allowed substitution hints:   𝜑(𝑥)   𝐹(𝑥)

Proof of Theorem fvelimad

Dummy variable 𝑦 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		fvelimad.c	. . . 4 ⊢ (𝜑 → 𝐶 ∈ (𝐹 “ 𝐵))
2		elimag 6064	. . . . 5 ⊢ (𝐶 ∈ (𝐹 “ 𝐵) → (𝐶 ∈ (𝐹 “ 𝐵) ↔ ∃𝑦 ∈ 𝐵 𝑦𝐹𝐶))
3	2	ibi 270	. . . 4 ⊢ (𝐶 ∈ (𝐹 “ 𝐵) → ∃𝑦 ∈ 𝐵 𝑦𝐹𝐶)
4	1, 3	syl 18	. . 3 ⊢ (𝜑 → ∃𝑦 ∈ 𝐵 𝑦𝐹𝐶)
5		nfv 1947	. . . 4 ⊢ Ⅎ𝑦𝜑
6		nfre1 3289	. . . 4 ⊢ Ⅎ𝑦∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶
7		vex 3457	. . . . . . . . . . 11 ⊢ 𝑦 ∈ V
8	7	a1i 11	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ V)
9	1	adantr 486	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → 𝐶 ∈ (𝐹 “ 𝐵))
10		simpr 490	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → 𝑦𝐹𝐶)
11	8, 9, 10	breldmd 5900	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ dom 𝐹)
12		fvelimad.f	. . . . . . . . . . 11 ⊢ (𝜑 → 𝐹 Fn 𝐴)
13	12	fndmd 6641	. . . . . . . . . 10 ⊢ (𝜑 → dom 𝐹 = 𝐴)
14	13	adantr 486	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → dom 𝐹 = 𝐴)
15	11, 14	eleqtrd 2864	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ 𝐴)
16	15	3adant2 1149	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ 𝐴)
17		simp2 1155	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ 𝐵)
18	16, 17	elind 4149	. . . . . 6 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → 𝑦 ∈ (𝐴 ∩ 𝐵))
19		fnfun 6636	. . . . . . . . 9 ⊢ (𝐹 Fn 𝐴 → Fun 𝐹)
20	12, 19	syl 18	. . . . . . . 8 ⊢ (𝜑 → Fun 𝐹)
21	20	3ad2ant1 1151	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → Fun 𝐹)
22		simp3 1156	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → 𝑦𝐹𝐶)
23		funbrfv 6930	. . . . . . 7 ⊢ (Fun 𝐹 → (𝑦𝐹𝐶 → (𝐹‘𝑦) = 𝐶))
24	21, 22, 23	sylc 66	. . . . . 6 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → (𝐹‘𝑦) = 𝐶)
25		rspe 3254	. . . . . 6 ⊢ ((𝑦 ∈ (𝐴 ∩ 𝐵) ∧ (𝐹‘𝑦) = 𝐶) → ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶)
26	18, 24, 25	syl2anc 596	. . . . 5 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵 ∧ 𝑦𝐹𝐶) → ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶)
27	26	3exp 1137	. . . 4 ⊢ (𝜑 → (𝑦 ∈ 𝐵 → (𝑦𝐹𝐶 → ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶)))
28	5, 6, 27	rexlimd 3271	. . 3 ⊢ (𝜑 → (∃𝑦 ∈ 𝐵 𝑦𝐹𝐶 → ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶))
29	4, 28	mpd 16	. 2 ⊢ (𝜑 → ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶)
30		nfv 1947	. . 3 ⊢ Ⅎ𝑦(𝐹‘𝑥) = 𝐶
31		fvelimad.x	. . . . 5 ⊢ Ⅎ𝑥𝐹
32		nfcv 2924	. . . . 5 ⊢ Ⅎ𝑥𝑦
33	31, 32	nffv 6892	. . . 4 ⊢ Ⅎ𝑥(𝐹‘𝑦)
34	33	nfeq1 2939	. . 3 ⊢ Ⅎ𝑥(𝐹‘𝑦) = 𝐶
35		fveqeq2 6891	. . 3 ⊢ (𝑥 = 𝑦 → ((𝐹‘𝑥) = 𝐶 ↔ (𝐹‘𝑦) = 𝐶))
36	30, 34, 35	cbvrexw 3307	. 2 ⊢ (∃𝑥 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑥) = 𝐶 ↔ ∃𝑦 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑦) = 𝐶)
37	29, 36	sylibr 237	1 ⊢ (𝜑 → ∃𝑥 ∈ (𝐴 ∩ 𝐵)(𝐹‘𝑥) = 𝐶)

This proof depends on syntax axioms:   → wi 4   ∧ wa 401   ∧ w3a 1103   = wceq 1570   ∈ wcel 2145  Ⅎwnfc 2909  ∃wrex 3088  Vcvv 3453   ∩ cin 3901   class class class wbr 5107  dom cdm 5659   “ cima 5662  Fun wfun 6531   Fn wfn 6532  ‘cfv 6537

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-sep 5255  ax-pr 5402

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ral 3079  df-rex 3089  df-rab 3415  df-v 3455  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-br 5108  df-opab 5172  df-id 5554  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-iota 6493  df-fun 6539  df-fn 6540  df-fv 6545

This theorem is used by:  cyc3evpm  33598  cycpmgcl  33601  cycpmconjslem2  33603  cyc3conja  33605  limsupmnflem  46556  liminfvalxr  46619