Theorem f1elima 5982

Description: Membership in the image of a 1-1 map. (Contributed by Jeff Madsen, 2-Sep-2009.)

Assertion

Ref	Expression
f1elima	⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴 ∧ 𝑌 ⊆ 𝐴) → ((𝐹‘𝑋) ∈ (𝐹 “ 𝑌) ↔ 𝑋 ∈ 𝑌))

Proof of Theorem f1elima

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		f1fn 5603	. . . 4 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹 Fn 𝐴)
2		fvelimab 5762	. . . 4 ⊢ ((𝐹 Fn 𝐴 ∧ 𝑌 ⊆ 𝐴) → ((𝐹‘𝑋) ∈ (𝐹 “ 𝑌) ↔ ∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋)))
3	1, 2	sylan 283	. . 3 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑌 ⊆ 𝐴) → ((𝐹‘𝑋) ∈ (𝐹 “ 𝑌) ↔ ∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋)))
4	3	3adant2 1047	. 2 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴 ∧ 𝑌 ⊆ 𝐴) → ((𝐹‘𝑋) ∈ (𝐹 “ 𝑌) ↔ ∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋)))
5		ssel 3242	. . . . . . . 8 ⊢ (𝑌 ⊆ 𝐴 → (𝑧 ∈ 𝑌 → 𝑧 ∈ 𝐴))
6	5	impac 381	. . . . . . 7 ⊢ ((𝑌 ⊆ 𝐴 ∧ 𝑧 ∈ 𝑌) → (𝑧 ∈ 𝐴 ∧ 𝑧 ∈ 𝑌))
7		f1fveq 5981	. . . . . . . . . . . 12 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑋 ∈ 𝐴)) → ((𝐹‘𝑧) = (𝐹‘𝑋) ↔ 𝑧 = 𝑋))
8	7	ancom2s 572	. . . . . . . . . . 11 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ (𝑋 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝐹‘𝑧) = (𝐹‘𝑋) ↔ 𝑧 = 𝑋))
9	8	biimpd 144	. . . . . . . . . 10 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ (𝑋 ∈ 𝐴 ∧ 𝑧 ∈ 𝐴)) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑧 = 𝑋))
10	9	anassrs 404	. . . . . . . . 9 ⊢ (((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ 𝑧 ∈ 𝐴) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑧 = 𝑋))
11		eleq1 2301	. . . . . . . . . 10 ⊢ (𝑧 = 𝑋 → (𝑧 ∈ 𝑌 ↔ 𝑋 ∈ 𝑌))
12	11	biimpcd 159	. . . . . . . . 9 ⊢ (𝑧 ∈ 𝑌 → (𝑧 = 𝑋 → 𝑋 ∈ 𝑌))
13	10, 12	sylan9 413	. . . . . . . 8 ⊢ ((((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ 𝑧 ∈ 𝐴) ∧ 𝑧 ∈ 𝑌) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
14	13	anasss 403	. . . . . . 7 ⊢ (((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ (𝑧 ∈ 𝐴 ∧ 𝑧 ∈ 𝑌)) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
15	6, 14	sylan2 286	. . . . . 6 ⊢ (((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ (𝑌 ⊆ 𝐴 ∧ 𝑧 ∈ 𝑌)) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
16	15	anassrs 404	. . . . 5 ⊢ ((((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ 𝑌 ⊆ 𝐴) ∧ 𝑧 ∈ 𝑌) → ((𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
17	16	rexlimdva 2668	. . . 4 ⊢ (((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴) ∧ 𝑌 ⊆ 𝐴) → (∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
18	17	3impa 1225	. . 3 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴 ∧ 𝑌 ⊆ 𝐴) → (∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋) → 𝑋 ∈ 𝑌))
19		eqid 2238	. . . 4 ⊢ (𝐹‘𝑋) = (𝐹‘𝑋)
20		fveq2 5698	. . . . . 6 ⊢ (𝑧 = 𝑋 → (𝐹‘𝑧) = (𝐹‘𝑋))
21	20	eqeq1d 2247	. . . . 5 ⊢ (𝑧 = 𝑋 → ((𝐹‘𝑧) = (𝐹‘𝑋) ↔ (𝐹‘𝑋) = (𝐹‘𝑋)))
22	21	rspcev 2929	. . . 4 ⊢ ((𝑋 ∈ 𝑌 ∧ (𝐹‘𝑋) = (𝐹‘𝑋)) → ∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋))
23	19, 22	mpan2 429	. . 3 ⊢ (𝑋 ∈ 𝑌 → ∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋))
24	18, 23	impbid1 142	. 2 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴 ∧ 𝑌 ⊆ 𝐴) → (∃𝑧 ∈ 𝑌 (𝐹‘𝑧) = (𝐹‘𝑋) ↔ 𝑋 ∈ 𝑌))
25	4, 24	bitrd 188	1 ⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝑋 ∈ 𝐴 ∧ 𝑌 ⊆ 𝐴) → ((𝐹‘𝑋) ∈ (𝐹 “ 𝑌) ↔ 𝑋 ∈ 𝑌))

This proof depends on syntax axioms:   → wi 4   ∧ wa 104   ↔ wb 105   ∧ w3a 1009   = wceq 1402   ∈ wcel 2209  ∃wrex 2529   ⊆ wss 3220   “ cima 4779   Fn wfn 5375  –1-1→wf1 5377  ‘cfv 5380

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-sep 4251  ax-pow 4313  ax-pr 4348

This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ral 2533  df-rex 2534  df-v 2823  df-sbc 3052  df-un 3224  df-in 3226  df-ss 3233  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-br 4132  df-opab 4194  df-id 4440  df-xp 4782  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-res 4788  df-ima 4789  df-iota 5340  df-fun 5382  df-fn 5383  df-f 5384  df-f1 5385  df-fv 5388

This theorem is used by:  f1imass  5983  iseqf1olemnab  10959  hashf1lem1  11307  fprodssdc  12382  ctinfom  13377  ssnnctlemct  13395  trlsegvdegfi  16913