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Mirrors > Home > NFE Home > Th. List > f1fveq | GIF version |
Description: Equality of function values for a one-to-one function. (Contributed by set.mm contributors, 11-Feb-1997.) |
Ref | Expression |
---|---|
f1fveq | ⊢ ((F:A–1-1→B ∧ (C ∈ A ∧ D ∈ A)) → ((F ‘C) = (F ‘D) ↔ C = D)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fveq2 5328 | . . . . . . 7 ⊢ (x = C → (F ‘x) = (F ‘C)) | |
2 | 1 | eqeq1d 2361 | . . . . . 6 ⊢ (x = C → ((F ‘x) = (F ‘y) ↔ (F ‘C) = (F ‘y))) |
3 | eqeq1 2359 | . . . . . 6 ⊢ (x = C → (x = y ↔ C = y)) | |
4 | 2, 3 | imbi12d 311 | . . . . 5 ⊢ (x = C → (((F ‘x) = (F ‘y) → x = y) ↔ ((F ‘C) = (F ‘y) → C = y))) |
5 | 4 | imbi2d 307 | . . . 4 ⊢ (x = C → ((F:A–1-1→B → ((F ‘x) = (F ‘y) → x = y)) ↔ (F:A–1-1→B → ((F ‘C) = (F ‘y) → C = y)))) |
6 | fveq2 5328 | . . . . . . 7 ⊢ (y = D → (F ‘y) = (F ‘D)) | |
7 | 6 | eqeq2d 2364 | . . . . . 6 ⊢ (y = D → ((F ‘C) = (F ‘y) ↔ (F ‘C) = (F ‘D))) |
8 | eqeq2 2362 | . . . . . 6 ⊢ (y = D → (C = y ↔ C = D)) | |
9 | 7, 8 | imbi12d 311 | . . . . 5 ⊢ (y = D → (((F ‘C) = (F ‘y) → C = y) ↔ ((F ‘C) = (F ‘D) → C = D))) |
10 | 9 | imbi2d 307 | . . . 4 ⊢ (y = D → ((F:A–1-1→B → ((F ‘C) = (F ‘y) → C = y)) ↔ (F:A–1-1→B → ((F ‘C) = (F ‘D) → C = D)))) |
11 | dff13 5471 | . . . . . . 7 ⊢ (F:A–1-1→B ↔ (F:A–→B ∧ ∀x ∈ A ∀y ∈ A ((F ‘x) = (F ‘y) → x = y))) | |
12 | 11 | simprbi 450 | . . . . . 6 ⊢ (F:A–1-1→B → ∀x ∈ A ∀y ∈ A ((F ‘x) = (F ‘y) → x = y)) |
13 | rsp2 2676 | . . . . . 6 ⊢ (∀x ∈ A ∀y ∈ A ((F ‘x) = (F ‘y) → x = y) → ((x ∈ A ∧ y ∈ A) → ((F ‘x) = (F ‘y) → x = y))) | |
14 | 12, 13 | syl 15 | . . . . 5 ⊢ (F:A–1-1→B → ((x ∈ A ∧ y ∈ A) → ((F ‘x) = (F ‘y) → x = y))) |
15 | 14 | com12 27 | . . . 4 ⊢ ((x ∈ A ∧ y ∈ A) → (F:A–1-1→B → ((F ‘x) = (F ‘y) → x = y))) |
16 | 5, 10, 15 | vtocl2ga 2922 | . . 3 ⊢ ((C ∈ A ∧ D ∈ A) → (F:A–1-1→B → ((F ‘C) = (F ‘D) → C = D))) |
17 | 16 | impcom 419 | . 2 ⊢ ((F:A–1-1→B ∧ (C ∈ A ∧ D ∈ A)) → ((F ‘C) = (F ‘D) → C = D)) |
18 | fveq2 5328 | . 2 ⊢ (C = D → (F ‘C) = (F ‘D)) | |
19 | 17, 18 | impbid1 194 | 1 ⊢ ((F:A–1-1→B ∧ (C ∈ A ∧ D ∈ A)) → ((F ‘C) = (F ‘D) ↔ C = D)) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ↔ wb 176 ∧ wa 358 = wceq 1642 ∈ wcel 1710 ∀wral 2614 –→wf 4777 –1-1→wf1 4778 ‘cfv 4781 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-13 1712 ax-14 1714 ax-6 1729 ax-7 1734 ax-11 1746 ax-12 1925 ax-ext 2334 ax-nin 4078 ax-xp 4079 ax-cnv 4080 ax-1c 4081 ax-sset 4082 ax-si 4083 ax-ins2 4084 ax-ins3 4085 ax-typlower 4086 ax-sn 4087 |
This theorem depends on definitions: df-bi 177 df-or 359 df-an 360 df-3or 935 df-3an 936 df-nan 1288 df-tru 1319 df-ex 1542 df-nf 1545 df-sb 1649 df-eu 2208 df-mo 2209 df-clab 2340 df-cleq 2346 df-clel 2349 df-nfc 2478 df-ne 2518 df-ral 2619 df-rex 2620 df-reu 2621 df-rmo 2622 df-rab 2623 df-v 2861 df-sbc 3047 df-nin 3211 df-compl 3212 df-in 3213 df-un 3214 df-dif 3215 df-symdif 3216 df-ss 3259 df-pss 3261 df-nul 3551 df-if 3663 df-pw 3724 df-sn 3741 df-pr 3742 df-uni 3892 df-int 3927 df-opk 4058 df-1c 4136 df-pw1 4137 df-uni1 4138 df-xpk 4185 df-cnvk 4186 df-ins2k 4187 df-ins3k 4188 df-imak 4189 df-cok 4190 df-p6 4191 df-sik 4192 df-ssetk 4193 df-imagek 4194 df-idk 4195 df-iota 4339 df-0c 4377 df-addc 4378 df-nnc 4379 df-fin 4380 df-lefin 4440 df-ltfin 4441 df-ncfin 4442 df-tfin 4443 df-evenfin 4444 df-oddfin 4445 df-sfin 4446 df-spfin 4447 df-phi 4565 df-op 4566 df-proj1 4567 df-proj2 4568 df-opab 4623 df-br 4640 df-co 4726 df-ima 4727 df-id 4767 df-cnv 4785 df-rn 4786 df-dm 4787 df-fun 4789 df-fn 4790 df-f 4791 df-f1 4792 df-fv 4795 |
This theorem is referenced by: f1elima 5474 f1oiso 5499 |
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