Theorem imaeqexov 7659

Description: Substitute an operation value into an existential quantifier over an image. (Contributed by Scott Fenton, 20-Jan-2025.)

Hypothesis

Ref	Expression
imaeqexov.1	⊢ (𝑥 = (𝑦𝐹𝑧) → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
imaeqexov	⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → (∃𝑥 ∈ (𝐹 “ (𝐵 × 𝐶))𝜑 ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝜓))

Distinct variable groups:   𝑥,𝐴,𝑦,𝑧   𝑥,𝐵,𝑦,𝑧   𝑥,𝐶,𝑦,𝑧   𝑥,𝐹,𝑦,𝑧   𝜑,𝑦,𝑧   𝜓,𝑥

Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦, 𝑧)

Proof of Theorem imaeqexov

Step	Hyp	Ref	Expression
1		df-rex 3088	. 2 ⊢ (∃𝑥 ∈ (𝐹 “ (𝐵 × 𝐶))𝜑 ↔ ∃𝑥(𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ∧ 𝜑))
2		ovelimab 7599	. . . . . 6 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → (𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧)))
3	2	anbi1d 643	. . . . 5 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → ((𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ∧ 𝜑) ↔ (∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑)))
4		r19.41v 3193	. . . . . . 7 ⊢ (∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ (∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
5	4	rexbii 3110	. . . . . 6 ⊢ (∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 (∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
6		r19.41v 3193	. . . . . 6 ⊢ (∃𝑦 ∈ 𝐵 (∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ (∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
7	5, 6	bitr2i 279	. . . . 5 ⊢ ((∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
8	3, 7	bitrdi 290	. . . 4 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → ((𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑)))
9	8	exbidv 1954	. . 3 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → (∃𝑥(𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ∧ 𝜑) ↔ ∃𝑥∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑)))
10		rexcom4 3290	. . . 4 ⊢ (∃𝑦 ∈ 𝐵 ∃𝑥∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑥∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
11		rexcom4 3290	. . . . . 6 ⊢ (∃𝑧 ∈ 𝐶 ∃𝑥(𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑥∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑))
12		ovex 7453	. . . . . . . 8 ⊢ (𝑦𝐹𝑧) ∈ V
13		imaeqexov.1	. . . . . . . 8 ⊢ (𝑥 = (𝑦𝐹𝑧) → (𝜑 ↔ 𝜓))
14	12, 13	ceqsexv 3499	. . . . . . 7 ⊢ (∃𝑥(𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ 𝜓)
15	14	rexbii 3110	. . . . . 6 ⊢ (∃𝑧 ∈ 𝐶 ∃𝑥(𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑧 ∈ 𝐶 𝜓)
16	11, 15	bitr3i 280	. . . . 5 ⊢ (∃𝑥∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑧 ∈ 𝐶 𝜓)
17	16	rexbii 3110	. . . 4 ⊢ (∃𝑦 ∈ 𝐵 ∃𝑥∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝜓)
18	10, 17	bitr3i 280	. . 3 ⊢ (∃𝑥∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 (𝑥 = (𝑦𝐹𝑧) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝜓)
19	9, 18	bitrdi 290	. 2 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → (∃𝑥(𝑥 ∈ (𝐹 “ (𝐵 × 𝐶)) ∧ 𝜑) ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝜓))
20	1, 19	bitrid 286	1 ⊢ ((𝐹 Fn 𝐴 ∧ (𝐵 × 𝐶) ⊆ 𝐴) → (∃𝑥 ∈ (𝐹 “ (𝐵 × 𝐶))𝜑 ↔ ∃𝑦 ∈ 𝐵 ∃𝑧 ∈ 𝐶 𝜓))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570  ∃wex 1812   ∈ wcel 2145  ∃wrex 3087   ⊆ wss 3899   × cxp 5649   “ cima 5654   Fn wfn 6533  (class class class)co 7420

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 2213  ax-ext 2733  ax-sep 5249  ax-nul 5260  ax-pr 5391

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 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-rab 3414  df-v 3453  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-iun 4953  df-br 5104  df-opab 5168  df-id 5546  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-iota 6494  df-fun 6540  df-fn 6541  df-fv 6546  df-ov 7423

This theorem is used by:  naddunif  8703